The script for the Photoshop Basic Workshop is intended exclusively for use in class at the University of Applied Arts Vienna and should serve as a reference work for all course participants. It may not be passed on to third parties.
Channels
Now let’s turn to a topic that is of great importance in Photoshop. Let’s talk about channels and masks. And for this we’ll open our edited exercise file 1.
> Go to My-Bsp1.psd.
We’ve already taken a look at the Channels palette several times in the workshop. So we know what we’ll find there. There is the composite channel, which represents the image as such. There are the color channels, which in sum again form the composite channel. And there are a couple of alpha channels, which we’ve come to know as stored selections. Let’s take a closer look at the latter now.
> Channels: Activate „Bucket_L“.
Alpha channels and masks
What are alpha channels?
Alpha channels are masks. What may not be obvious at the beginning becomes immediately clear when we look again at what the selection creation as such does. The selected part or aspect of the image is accessible to editing, all parts not selected are excluded from editing. So the selection itself is already a mask and an alpha channel is nothing more than its fixation.
We can also visualize the facts by an example from nature. Let’s think of a classic stencil – a piece of cardboard in which we have cut a hole with a pair of scissors. Let’s place the cardboard on a sheet of paper and go over it with a spray can. Where the cardboard has a hole, paint is applied, all other areas are spared from paint application. With this we have described the basic principle of a mask.
And now a question that may seem strange at first, but the answer to which will help enormously in understanding how the alpha channels work: What is the color depth of the classical stencil just described?
The classic stencil has a color depth of 1 bit. It allows exactly two states.
1 bit is the smallest unit of information, the atom of the binary system.
1 bit combines the possibility of two opposing states: zero and one, yes and no. Yes, the hole in the mask that allows color to be applied, No, the mask itself that prevents color to be applied.
And also the contrast of black and white, which seems to characterize our alpha channel at first glance, contains the information content of 1 bit. The white pixels of the channel stand for complete selection, the black pixels stand for non-selection.
> Zooming in on the mask contour.
A closer look, however, reveals a fact that we might have already guessed: An alpha channel is not just white and black pixels. In fact, grayscales of varying intensity can be found here.
An alpha channel can contain up to 256 different gray levels, because, as we already know, a channel has a color depth of 8 bits/pixel. 2 to the power of 8 equals 256.
An alpha channel is therefore not a classic stencil, but a mask that can be used to capture complex selection states.
- White pixels in the channel represent a complete selection.
- Areas with black pixels do not generate a selection.
- And the gray levels between these two extreme values generate more or less strong selections, depending on the brightness. The brighter, the stronger the selection will be, the darker, the weaker.
> Fit to Screen via cmd+0.
Let’s illustrate the effects of this with a concrete example. Let’s create a gradient from black to white in a new channel.
> Activate the gradient tool, Foreground to Background.
> Set Foreground color and Background color to black and white by pressing the D key.
> New alpha channel via button Create new channel.
> Drag the gradient diagonally over the entire channel area.
Now we have to load the content of the channel as selection. And this in the usual way.
> Select / Load Selection: Channel Alpha 1 and OK.
With a click on the composite channel we switch back to the image and pour any foreground color into the selection via Option+backspace for demonstration.
> Click composite channel.
> Fill area via option+backspace.
The fill result clearly shows how the different gray levels of the alpha channel correspond to the different selection intensities. Please compare the color application in the image with the gradient shown in the channel thumbnail: Where white channel pixels are located, 100% color is applied. Where black channel pixels are located, the image is spared from color application. The various gray levels of the gradient are more or less affected by the color.
> Undo via cmd+Z, deselect via cmd+D.
By clicking on the bar of the gradient channel we return to the mask environment.
> Channels palette: click Alpha 1 bar.
The active channel appears highlighted in the Channels palette. It is important to always pay attention to which channel you are in, because only the active channel can be edited.
Currently Alpha 1 can be edited.
> Click on the composite channel bar in the Channels palette.
If we activate the composite channel, it and the three color channels are highlighted and we can edit the image.
I say the obvious overly clear, because at the beginning of the discussion with alpha channels, or masks, there is the danger to lose the orientation and not to become aware of the principle difference between image and mask.
> Channels palette: Activate alpha 1.
Now I am back in the channel and the mask can be modified.
If the application of a tool or feature in Photoshop does not work as expected, the reason could be that it is done in the wrong channel.
So the second entry on the quick troubleshooting checklist is: am I in the right channel? A look at the Channels palette should clarify that.
Selecting using masks
In the course of creating the gradient mask, we casually learned about a powerful selection technique all its own. Until then, we thought of alpha channels simply as saved selections. Now we have learned that alpha channels can be used in the reverse way to create selections themselves.
Now let’s take a closer look at the concept and workflow of creating selections using a painting tool.
Once again, we’ll start with a new, empty channel. I create a new channel by clicking on the Create new channel icon at the bottom of the Channels palette.
> Create new channel.
I said the channel is empty. But this is not really an accurate expression. In fact, the channel is filled with black pixels without exception. We already know: zones marked by black pixels in the channel will not be selected. So if we were to load this new channel as a selection, nothing would be selected in the image.
To create a selection using the channel, we now need to do nothing more than create white or light zones in it. I had used the Gradient tool for this earlier. Now I use the Brush Tool to apply white color.
> Activate Brush Tool.
I make sure I have selected white as the foreground color. To be sure, I press the D key.
> Press the D key.
In mask environment, simply pressing D sets the foreground color to white and the background color to black. That’s exactly how we want it here for now.
Pressing the D key, by the way, is equivalent to clicking on the little black and white icon to the left above the Color Picker in the toolbox.
I could now immediately start brushing in the channel to scratch a hole in the mask. But I’m pursuing a very specific selection goal. And that requires a few more preparatory steps.
Since I’ve set out to select our little bucket with this technique, I need to bring it to view somehow beforehand. Through the closed mask, I might just be able to guess where it is. No chance of brushing an exact selection.
To bring the image to view, I click in the area to the left of the composite channel thumbnail.
> Show Composite Channel.
An eye icon appears at the clicked location and the three color channels also get one immediately. The image is now faded in.
Please pay close attention to the markings in the Channels palette:
- The four eye symbols indicate that the image is visible. However, the bars of the composite channel and its three color channels are not highlighted. This means they are not activated and therefore cannot be affected by any action we set in the sequence.
- Alpha 1 is also visible, which means we can see its contents. However, instead of black, blue signal color appears. The mask color is used solely for better differentiation, so it has no meaning in itself. I will explain this aspect in more detail later.
The channel bar of Alpha 1 is highlighted. And this means the channel is activated and can be edited.
Once these first preparatory steps are done, I zoom in on the subject to be selected and take care of the tool settings of the Brush Tool.
> Zoom in on the bucket via cmd+Spacebar-drag.
Since the bucket has a relatively hard, smooth contour, we need to create a tool tip that meets these requirements. We remember that we have already created and saved exactly such a tool tip – our so-called clipping tip. So all I have to do is activate it in the Brushes palette and I’m ready to go.
> Open the Brushes palette and activate “Clipping_30px-90h-15sp”.
The hardness reduced to 90% takes into account the fact that absolutely hard contours do not exist in photos. You can see this clearly in the outline of the bucket. If we wanted to be completely accurate, some contour areas would have to be captured with an even softer tool tip. Please pay attention to the lower sweep of the bucket’s contour, which actually protrudes into the blur area.
In the workshop we will ignore this, in practice it must be taken into account if we want to achieve an accurate result.
The contour may not be completely hard anywhere, but it is always smooth. We react to the smoothness of the contour we want to capture by reducing the spacing in the brush stroke. The 15% spacing of our clipping tip is perfectly adequate here.
Only the size of the clipping tip with its diameter of just 30 pixels should be modified in view of the situation.
> Size 100px via ctrl-option-drag.
Now nothing stands in the way of selecting the bucket.
> Capture the contour of the bucket with short shift-clicks.
I select the bucket by applying white. Where I use the brush, the blue mask color disappears. This is the indication that my actions are successful.
> Intentionally brush over the contour.
Small mistakes, like the one we just made, can be quickly corrected by applying black to close the mask again. If the foreground color and background color are set to black and white, all I have to do is swap the two. I achieve this quickly by pressing the X key.
> Press the X key several times, last foreground color black.
The keyboard command corresponds to a click on the small button with the bend arrow symbol right above the Color Picker.
> Close the mask at the position where you want it to be.
> Press the X key.
After the correction is done, I press the X key again and continue selecting.
Since exact freehand brushing with the mouse is almost impossible, I do the whole thing quasi semi-automatically by densely setting shift clicks. Which work tool would pay off instead of the mouse for tasks like this? Again, a pen tablet.
When working with a pen, we use the fine motor skills of our fingers and hand to achieve precise guidance. Something we can’t achieve with the mouse. Professional image editors and graphic designers swear by working with the pen tablet but also for other reasons …
- For one thing, some features in Photoshop are only accessible to the pen.
I mentioned this earlier in the workshop. - Secondly, working with a pen tablet also has ergonomic advantages. The dreaded mouse shoulder or head, neck or back pain, all these typical complaints can usually be avoided by using a pen tablet.
Once the outline is captured, I add the interior to the selection. I can also do these remaining steps with the Brush Tool, or I can reach for the Lasso.
> Activate Lasso and generously capture the interior via option-clicks.
> Fill area via option+Backspace.
> Unselect via cmd+D.
> Fit to Screen via cmd+0.
Finally I undo the temporary lasso selection and look at my work: The bucket is now completely free of mask color.
> Hide composite channel.
If I hide the composite channel to get a clear view of the alpha channel, I see the actual result: I have brushed a white spot into the black of the mask.
I also give this channel a relevant name:
> Double-click channel name, entry “Bucket_B”.
Whether the brushed selection does what it is supposed to, only becomes apparent in the application. I return to the picture for this. Currently we are still in the channel.
> Click on the composite channel bar.
A faster way is to Cmd-click on the channel bar. I position the cursor anywhere in the bar of the channel whose selection is to be loaded.
> Press the Cmd key in the channel bar to load the selection.
As soon as I press the command key, a selection icon appears on the cursor. A short Cmd-click activates the selection.
> Deselect again.
Now let’s take a look at the channel options.
> Open channel options by double clicking on the new channel bar.
We can also enter the channel name in the channel options. More interesting, however, are the other sections of this little dialog.
- With Color Indicates we determine which aspect the mask color indicates. Should the signal color stand for the mask or for the selection area? The default setting for alpha channels is Masked Areas. I think this is reasonable and suggest keeping it.
- Using the Color Picker, we can specify any mask color. In any case, the mask color should be different from the color of the subject to be selected. In our image, for example, a red mask color would not be very useful. We would hardly be able to determine where we still have to edit the mask when selecting the red bucket.
However, the default mask color in Photoshop is a strong red. I personally prefer a strong blue, not only in our case, but in general.
> Open Color Picker.
Experience shows that in image editing, one encounters a strong red far more often than a flash blue. In other words, a blue mask color is less likely to encounter blue subjects that are to be selected. And that means the blue mask color needs to be modified less often than the red mask color.
If you want, you can follow me on this point and choose a blue mask color.
> Close Color Picker.
The opacity of the mask color is chosen very reasonable with 50%. The reduced opacity makes it possible to see through the mask.
> Close Channel Options with OK.
Perhaps one or the other of you is now asking the legitimate question: Why should I choose this rather cumbersome procedure with alpha channel and Brush Tool, when I can create the selection in the shortest possible time with the Object Selection Tool?
The answer to this question is provided by a closer look at the qualities of the different selection techniques.
I remove the gradient channel, since we don’t need it any further. Then I activate the channel Bucket_L and zoom in on the relevant zone.
> Delete the gradient channel by dragging it onto the palette trash can.
> Activate Bucket_L.
> Zoom in on the bucket selection.
Now the hours of truth strike. In the sequel, please pay close attention to the sometimes completely different contour qualities that the different selection techniques bring.
Lasso selection:
The lasso selection is very hard, as we have refrained from setting a soft edge. Another very noticeable feature is a certain angularity of the contour.
How did this come about?
The angularity results from the fact that we took advantage of the tool’s polygon effect when creating the selection.
The Lasso tool is, as I said, primarily suitable for creating rough preselections.
> Activate Bucket_O.
Object Selection Tool selection:
The Object Selection Tool usually provides a quite usable selection of motifs. All specific contour properties were taken into account during the selection process.
If the bucket is left in place, there is nothing wrong with the AI-assisted object selection. If the object is to be transposed, i.e. used in a different place in the image or in another document at all, the weaknesses of this over-accurate selection technique become apparent. The contour of the object appears eroded. The flaw is clearly visible.
> Activate Bucket_Q.
Quick Selection Tool selection:
It is quite similar with the selection qualities of the Quick Selection Tool. As long as the selected object remains in its original environment, all fine. When transposed, the selection does not do justice to the basically smooth outline of the bucket.
To prevent a possible misunderstanding: motifs with rough contours can be transposed quite wonderfully. Both the Object Selection Tool and the Quick Selection Tool sometimes provide quite useful selections of motifs with irregular contours. And moving the objects into other contexts does not cause any problems. Only motifs with decidedly smooth contours, like our little bucket, or very complex, hairy contours are problematic here.
> Activate Bucket_B.
Brush Tool selection:
The brushed selection is characterized by a reduced hardness and, if well brushed, appears otherwise smooth. The brush thus proves to be the perfect tool for selecting subjects with hard, smooth outlines.
The only thing that makes it a bit awkward is creating an alpha channel. However, we’ll soon learn a technique to shortcut this little awkwardness.
Before that we have to deal with the mask operations.
> Activate image by clicking on the composite channel.
Mask operations
You remember the familiar key commands for combining selections:
- If another selection is to be added to an existing selection, we hold down the Shift key during the selection process.
- If we want to deselect a part of an existing selection, we hold down the Option key during the deselection process.
- If the intersection of two selection areas is to be formed, we press the Shift and Option keys together.
The same key commands allow to conveniently bring out the said selection combinations while loading a selection from a channel. For this purpose, only the Cmd key must be pressed additionally. It takes care of loading the selection.
I would like to demonstrate the whole thing by means of the deselection process.
> Load selection bucket_B via cmd-click.
> Zoom in on bucket and shadow zone.
> Fill area with contrasting foreground color.
After recoloring an image element, you will very often find that the immediate surroundings also need to be adjusted in color. In the shadow area below the bucket, a red tint is clearly noticeable. Of course, this comes from the original red of the bucket and must be recolored accordingly.
> Undo by pressing cmd+Z.
> Unselect by cmd+D.
Since we only want to capture the red tint in the shadow area of the bucket, we need to create a shadow selection.
For this I create a new alpha channel and capture the soft outer contour of the shadow there with a round soft tip.
> Create new channel.
> Show composite channel.
> Activate Brush Tool, round, soft tip, size approx. 200px.
> Alpha 1: Brush the outer contour of the shadow.
You see, for now I’m just trying to accurately capture the outer contour of the shadow area. Why I can safely ignore the effects on the area of the bucket will become clear in a moment.
I now load the selection I just brushed via Cmd-click of the channel bar of Alpha 1.
> Load selection from Alpha 1 via cmd-click.
The bucket zone must not be part of the shadow selection, of course. Since I can fall back on an already saved selection of the bucket, it is easy to achieve the perfect shadow selection by subtracting the bucket selection. And I do this in the following way …
I position the cursor somewhere in the channel bar of bucket_B and press the Command key, which as we already know will cause the selection to be loaded from the channel.
> Bucket_B: Press the Cmd key.
As usual, the selection icon will appear in the cursor. Please pay attention to how the selection symbol changes as soon as I now additionally press the Option key for the deselection process.
> Bucket_B: Pressing the Cmd and Option keys.
A small minus sign appears in the selection symbol. In words, this means that if you click the channel bar while holding down the Cmd and Option keys, the channel selection will be subtracted from the selection active in the image.
That’s exactly what we want, and that’s exactly what I’m doing now.
> Clicking the channel bar of Bucket_B while holding down the Cmd and Option keys.
In the same way, the other two selection combinations can be achieved. We always just have to hold down the Cmd key in addition to the key command of the respective selection combination and click the channel bar whose selection is to be loaded.
This is how adding works …
> Alpha 1: Load selection by Cmd-click.
> Clicking the channel bar of bucket_B while holding down the Cmd and Shift keys.
And this is how the intersection works …
> Alpha 1: Load selection by Cmd-click.
> Clicking the channel bar of Bucket_B while holding down the Cmd, Option and Shift keys.
So the commands to combine an active selection with a mask selection are:
- Cmd-shift-click to add the mask selection to the active selection.
- Cmd-option-click to subtract the mask selection from the active selection.
- Cmd-option-shift-click to intersect the mask selection and the active selection.
> Delete alpha 1.
Sure, we could have had the whole thing simpler. By the way, this is also true for brushing masks in general. However, there is a didactic reason why I would like to introduce you to mask creation, mask editing and mask combinations using the alpha channels: In fact, every conceivable pixel mask that we can encounter in Photoshop is always an alpha channel, even if this should not be obvious at first glance. In a sense, the terms alpha channel and mask are synonymous.
Now, let’s learn a technique that allows us to create masks without having to create an alpha channel.
Quick Mask Mode
Let me introduce you to Quick Mask Mode. As the name suggests, Quick Mask Mode is designed to speed up mask creation.
I activate the Quick Mask Mode by pressing the Quick Mask Mode button, which can be found in the toolbox just below the two Color Pickers.
> Activate Quick Mask Mode.
Once the button is highlighted, we are in Quick Mask Mode. And that means we are no longer in the image, but in the mask environment. Every brush stroke that is now set contributes to the mask design.
A look at the Channels palette proves that this is the case. Switching from Normal Mode to Quick Mask Mode has created a new alpha channel there, the name of which makes sense to be “Quick Mask”.
It may irritate us that the Quick Mask Channel, in contrast to the alpha channels, is filled with white at the beginning. But the circumstance is quickly explained. The reason for this is that we proceed in reverse when creating a Quick Mask. We don’t scratch a hole in the mask color, but we brush the selection positively. We make the appropriate setting for this once and for all in the Quick Mask Options.
A double click on the Quick Mask Mode button opens the Quick Mask Options.
> Open the Quick Mask Options by double-clicking on the Quick Mask Mode button.
Unlike in the Channels, the Selected Areas should be marked by color. This makes the application easier. You will understand immediately how this is meant.
> Close Quick Mask Options with OK.
We are still in Quick Mask Mode. I grab the brush and set the foreground color to black.
> Activate Brush Tool.
> Set the foreground color to black by pressing the D key.
> Set any brush stroke.
By applying black with the brush, I leave blue traces. This will not surprise us, because we know that we are not working in the image, but in mask environment.
Once I have covered all the areas to be selected with blue selection color, the only thing left to do is to return to Normal Mode to complete the selection process.
> Deactivate Quick Mask Mode.
As soon as I press the Quick Mask Mode button again to return to normal mode and thus to the image, the Quick Mask Channel disappears from the channel palette and the desired selection is active.
The Quick Mask Channel is therefore a temporary alpha channel. And exactly this circumstance speeds up the selecting process immensely.
> Unselect with cmd+D.
And using the key command Q to activate the Quick Mask Mode is even a bit faster: Press Q key, brush, press Q key again, done.
> Activate Quick Mask Mode via Q key.
> Brush any selection.
> Deactivate Quick Mask Mode via Q key.
Let’s practice creating a selection using Quick Mask Mode a bit more. Our selection target is the number “2”, which can be seen at the bottom of the bucket.
> Activate Quick Mask Mode via the Q key.
> Activate Brush Tool, tool tip size 10px, hardness 50%.
> Brush the contour of the “2” at the bottom of the bucket.
> Paint a little beyond it at one point.
Mistakes that you make while brushing can be quickly corrected by changing the foreground color to white. Since I have set the foreground and background colors to black and white, just press the X key to make the change.
> Swap foreground and background color via X key.
> Correct errors in the mask.
> Swap foreground and background color via X key.
> Complete the contour of the “2” at the bottom of the bucket.
Once I have captured the contour of the selection area, I like to add the inside to the selection via a small workaround.
> Activate Magic Wand Tool, Tolerance 50%, checkbox Contiguous on.
> Click the missing interior.
> Select / Modify / Expand by 5 Pixels and OK.
> Fill area with black via option+Backspace.
> Deactivate Quick Mask Mode via Q key.
Besides increasing the speed of selecting, working with Quick Masks offers another advantage that is not insignificant. Since Quick Mask Channels are temporary alpha channels, of which nothing but the current selection remains after returning to normal mode, no unnecessary alpha channels accumulate in the Channels palette. The number of alpha channels is not limited, but each additional channel increases the file size.
We can see this fact in the bottom left corner of the info bar of the window. There, the right value has grown considerably compared to the left value. This increase is caused by the four alpha channels that are currently present in the file.
In conclusion, I would like to state once again that with the Brush Tool and the possibilities offered by the masks, we have in our hands a powerful selection technique that is frequently used.
We have now been introduced to a number of selection techniques in Photoshop. I hope that by now it has become clear how important it is to master different selection techniques. Each selection tool and feature is used in typical use cases. We need to master them all if we want to make progress in image processing.
Having reached this point, let’s leave selection creation alone for now and turn to another important topic in Photoshop.
Layers
Besides the Channels and the Paths, the Layers palette is part of the bundle of the main palettes.
> Switch to the Layers palette.
Since all image processing steps are reflected in the Layers palette, it should always be displayed. Only when we work in the channels or create paths, we turn our eyes away from it for a short time.
At this point, the Layers palette still seems a bit empty. So far there is only one layer there, the background layer. I have already mentioned that the background layer is a special layer. It contains the image in its original state, before any editing.
I have also already mentioned the reasons why we strive to preserve this original state. The original should serve us as an unedited reference – during image processing, but also beyond.
Tastes and requirements change from time to time. If one has kept the unaltered original in the backhand, changes to the processing at a later time can always take their starting point from the original state. It will then not be necessary to contact the photographer again to request the original once more. Btw: The photographer is not obliged to archive the images beyond a due period of time.
In a word, we always leave the background layer untouched without exception.
The background layer acts as the bottom sheet in the layer stack. All editing is done separately in layers above it. And that’s how we need to think of the perfect Photoshop master: The background layer at the bottom, above it the retouching layers, the image montage layers, the adjustment layers where we take care of color values and tonal values, the text layers, painting layers, illustration layers, etc. The structure of the Photoshop master depends, of course, on the requirements of the particular image processing.
New Layer
We already know how to create a new, empty layer.
> Create a new layer by clicking on the New button at the bottom of the Layers palette.
The new layer is called „Layer 1″ and hovers directly above the background layer, since it was active last time. Now the new layer is active and can be edited. This is indicated by the highlighted layer bar.
If you click the New button while holding down the Cmd key (Windows: right click), the new layer will be inserted below the active layer.
> Create a new layer via Cmd-click of the New button.
> Delete the new layer again by dragging the layer bar to the trash can symbol of the layer palette.
> Hide background.
Let’s hide the background layer to examine the contents of the new layer alone. The gray checkerboard pattern represents transparency. Where the checkerboard pattern appears, there are no pixels.
> Activate Brush Tool, any tool tip and foreground color.
> Set brushstroke.
We set our brushstroke in the empty layer and create pixels with it.
> Show Background again.
We already know this procedure. And we already know about the possibilities to adjust the content of the layer.
> Open the Blending Mode menu and go through it, last Multiply.
If the Blending Mode menu, the Opacity slider and the Fill slider are operated, this has an effect on the active layer.
We can change the opacity by moving the slider manually.
> Open the Opacity slider by clicking on the arrow.
We can also change the value gradually. Clicking activates the value, which can then be increased by pressing the Up key and decreased by pressing the Down key. If we hold down the Shift key during the process, the change is made in steps of ten.
> Click on the opacity value and change it by pressing the up and down arrow keys.
> Change the opacity value by shift-pressing the up and down arrow keys, finally 50%.
If we are not satisfied with the result, we hide the layer or dispose of it completely by pressing the delete key or clicking on the trash can icon at the bottom of the layer palette.
> Hide Layer 1 and delete it last.
And the nice thing is that the little episode left no traces on the original.
Working with retouching tools in separate layers is already familiar to us and does not need to be discussed further at this point. If parts of the image are to undergo a massive change, this must also be carried out in layers that are separate from the background layer.
Layer Via Copy
Now, without much ado, let’s recolor the red bucket. To protect the background layer and the rest of the image from our intervention, we activate one of the saved selections and place a copy of the bucket in a new layer.
> Switch to the Channels palette.
> Cmd-click Bucket_O.
Before returning to the Layers palette, make sure that only the composite channel and its individual color channels are active and none of the alpha channels are active or visible. After all, we want to do our editing in the layer, i.e. in the image, and not in a channel. The channels have already done their job by loading the required selection.
> Return to the Layers palette.
A copy of the selected pixels should now be placed in a new layer for editing.
> Layer / open New menu.
The New entry of the Layer menu offers us a number of possibilities to create layers. At the top you will find the command to create a new, empty layer. Layer from Background turns the background layer into a real layer, etc.
Currently, however, we are only interested in one particular entry of the New Layer menu: Layer Via Copy.
Layer Via Copy, as the name suggests, puts a copy of the selected pixels into a new layer. Since we will be doing this very often, we should remember the shortcut Cmd+J well. Let’s apply this shortcut right away.
> Close Layer menu and Layer Via Copy by cmd+J.
The marching ants disappear and a new layer appears in the Layers palette. We check its contents by temporarily hiding the background layer and find that our wish has been fulfilled: A copy of the bucket pixels is in its own layer.
> Hide the background layer and show it again.
> Hide layer 1 and show it again.
The copy comes to lie exactly on top of the original. Hiding and unhiding the new layer does not change the appearance.
Double-clicking on the label Layer 1 allows us to name the new layer.
> Double-click “Layer 1”, replace it with “Bucket”.
We should make an accurate naming, so do not choose a fantasy name. The name should indicate the content, so that we can quickly identify the layer at a later time, since it will be one among many.
And the bucket really deserves the correct name now. Only now, when the pixels of the motif are available separated in their own layer, we can call the motif an object with some justification.
Edit layer content
Now that we have done all the preliminary work, we can get down to editing. I would like to show you three different scenarios.
Mind you, the recoloring is only for illustration purposes and we will get to know some better techniques for this later. Currently, we are only interested in the effects of the application on the pixels of the new layer.
I open the Fill dialog and select Foreground Color, Mode Color and 100% Opacity.
> Edit / Fill / Contents Foreground Color, Mode Color, Opacity 100%, uncheck Preserve Transparency and OK.
The bucket is colored, but unfortunately so is the rest of the layer. If I want to make sure that only the pixels present in the layer are affected by the processing, but not the transparent areas, it is necessary to exclude the latter. Photoshop offers three ways to do this.
> Undo by Cmd+Z.
> Edit / Fill / Check Preserve Transparency and OK.
The small Preserve Transparency checkbox of the Fill dialog protects the transparent areas of the layer from editing. This is quite practical, but only available in the Fill dialog.
> Undo with cmd+Z.
Fortunately, the transparent areas can also be protected in general by an action in the Layers palette.
A click on the small transparency symbol of the palette (Lock transparent Pixels) ensures that the transparent pixels of the current layer cannot be affected by any editing action whatsoever.
> Activate Lock transparent Pixels.
> Activate Brush Tool, any tool tip.
> Drag brushstroke across the image and the bucket.
> Press cmd+Z.
For the sake of completeness, it should be mentioned that the other Lock buttons in the Layers palette can be used to lock some other aspects of image editing.
The button with the brush symbol prevents editing of the current layer in general.
> Activate Lock Image Pixels.
> Set Brushstroke.
The button with the move symbol freezes the layer content in place. So the pixels of the layer can’t be moved anymore.
> Activate Lock position.
> Activate Move Tool and try to move layer content.
With the exception of Lock transparent pixels, however, these locking options are rarely used, as they tend to hinder the workflow rather than being useful.
> Unlock everything.
Layers and selections
Now let’s take a look at the third and perhaps most obvious scenario for protecting transparent pixels: Activating the bucket selection.
However, I do not use one of the saved selections, but choose a shorter way. Please pay close attention to my procedure.
I position the cursor in the thumbnail of the layer whose pixels I want to select. As soon as I press the Cmd key, the selection symbol appears at the cursor. Clicking on the thumbnail while holding down the Cmd key activates the selection of all pixels of a layer that are not transparent.
> Bucket layer: Cmd-click on the thumbnail.
> Hide background and then show it again.
We have now learned something very important: It is not always necessary to save a selection that is to be accessed again at a later time specifically as an alpha channel. If an image part exists separated in its own layer, the activation of its selection is only a Cmd-click away.
Since all image processing is done in layers, if you handle this principle skillfully, you can always access the area selections you need. Now this is really handy.
> Unselect via cmd+D
Move Tool
Since I have reached for the Move Tool earlier, let’s take a closer look at how it works.
I like to call the Move Tool the actual layer tool, because its main task is to move the layer content.
> Moving a bucket with the Move Tool.
This doesn’t sound very spectacular, and it is. However, I would like to make a few remarks about the handling of the Move Tool, since it is one of the most used tools in the toolbox. And for this reason, I also strive to use it accurately.
The two checkboxes Auto-Select and Show Transform Controls of the tool’s options bar always remain deactivated for me. Just for the sake of completeness, I’ll briefly mention what they are about.
- Auto-Select makes it possible to immediately activate the layer that has pixels at that position by a single tool click. What sounds practical fails in practice as soon as many layers overlap each other in a confusing way. However, this is the normal state.
- The Transform Controls are useful when transforming, i.e. scaling, rotating or distorting parts of the image. If such operations are triggered, the Transform Controls are available at the right time anyway. In all other image processing contexts, they merely interfere with the view.
Since we will need the tool very often, let’s practice three important key shortcuts right from the start.
> Activate Brush Tool.
> Activate Move Tool by pressing the V key.
The Move Tool is activated by pressing the V key in the toolbox.
Changing tools takes time. However, the Move Tool is one of those tools that can be used temporarily in Photoshop without having to be specifically activated in the Toolbox.
> Activate Brush Tool.
> Activate Move Tool by holding down Command.
> Move Bucket Tool.
We keep the current tool in hand, press the Cmd key, move the layer content, then release the Cmd key again and can immediately continue our work with the original tool.
And a third key command also proves to be quite useful for working with the Move Tool: we cause the movement to be restricted to the orthogonal or diagonal axes by holding down the Shift key.
> Move the bucket orthogonally and diagonally while holding down the Shift key.
Finally, a small, practical feature of the Move Tool should be mentioned.
> Activate Move Tool by pressing the V key.
> Adjust the opacity of the layer by entering a number, last again 100%.
If the Move Tool is activated in the toolbox, the opacity of the layer can be adjusted in steps of ten by simply entering a number. Pressing the 0 key sets the opacity to 100%.
> Keep pressing cmd+Z until the bucket is back in its original position.
Layer hierarchy
Now I want to create a layer that contains the little shovel. For this I use the lasso.
> Activate Lasso and create a rough preselection of the little shovel.
> Layer via Copy by Cmd+J.
Photoshop tells us that no new layer could be created, because the selected area is empty.
The reason is: we are simply in the wrong layer.
> Hide background.
In the bucket layer, there are no pixels where we would expect to find the shovel. So there was no material that could have been selected. We must, of course, activate in advance that layer which actually contains the targeted pixels.
And so the third entry on the checklist for quick troubleshooting is: Am I in the right layer? A look at the Layers palette should clarify that.
> Show and activate Background again.
> Select shovel with the Object Selection Tool.
> Layer via Copy by cmd+J.
> Layer-Name: “Shovel”.
In the Layers palette, in addition to the background layer, there are now two real layers that have all the attributes we can expect from a layer: Their content is freely movable and there are transparencies.
If I move the shovel layer with the Move Tool to the left, the shovel partially disappears behind the bucket.
> Move the bucket with the Move Tool.
This is caused by the layer hierarchy, of course. One layer is below the other layer in the Layers palette, so its content appears spatially behind the content of the other layer in the composite view of the image.
If we swap the two layers in the hierarchy of the layer palette, the little shovel moves spatially in front of the little bucket in the image.
> Position the bucket layer below the shovel layer.
By manipulating the layer hierarchy in the layer palette, we thus change the spatial relationship between the image parts. This ability to create an artificial before and behind in an arrangement of layers forms the basis for something we call image montage.
> Move the shovel to the right into the gravel bed.
Strictly speaking, we have not yet accomplished a real montage. Like with a pair of scissors, we have just cut out a part of the image and pasted it into the picture. So at the moment we have to speak more of a collage.
What does the collage lack to be a montage?
The montage is characterized by the fact that all spatial and local aspects are included, i.e. artificially created. The lighting situation, the casting of shadows, changes in color, reflections, perspective, and much more must be precisely designed for a perfect image montage in order to ultimately produce a realistic impression of the composition.
We will deal with the very important topic of image montage in detail at a later time. For now, it’s just a matter of getting to know the basic dispositions.
Layer Handling
Let’s explore layer handling further.
> Remove shovel layer by pressing the delete key.
> Move bucket layer up a bit.
If we want to duplicate a layer, we drag the layer bar to the Create a new Layer icon of the Layers palette. We can do this more quickly by holding down the Option key while the Move Tool is active and moving the layer contents.
> Move the bucket a bit to the top right while holding down the Option key.
In fact, the Move Tool does not even need to be activated itself for this operation. Using the Cmd-option-move short cut, we can duplicate a layer without having to pay attention to which tool is currently active.
> Activate Brush Tool.
> Move the bucket to the lower right corner while holding down the Cmd-option keys.
The Command key temporarily activates the Move Tool and the Option key is responsible for duplicating. When the process is done, we release the keys and the originally selected tool is available again. It is therefore not necessary to change tools to duplicate layers.
If the content of a particular layer is to be edited, the layer must be activated. We can do this by clicking on the corresponding layer bar or directly in the image using the Move Tool.
To do this, we activate the Move Tool in the toolbox and click the intentional layer content while holding down the Cmd key.
> Activate Move Tool via V key.
> Cmd-click left bucket.
As soon as we press Command, Auto-Select appears checked in the Move Tool options bar. So we use Auto-Select temporarily and exactly at the time we need this function.
Let’s create a few more duplicates of the bucket.
> Create five more duplicates of the bucket.
If you want to move, delete or group several layers in the image, you have to activate them at the same time. Holding down the Shift key allows you to activate a number of layers in the Layers palette. We first activated the layer that should be the beginning of the row.
> Activate the fourth bucket layer.
With a shift-click of the layer that should form the end point of the row, we finish the activation.
> Shift-click the top bucket layer.
> Move the activated layers a little with the Move tool.
If, on the other hand, several layers that do not form a row are to be activated for a common action, we do not use the Shift key, but the Cmd key.
> Activate the fourth bucket layer.
> Activate the sixth and eighth bucket layers via Cmd clicks.
> Move the activated layers a bit with the Move Tool.
For the next task, we will now delete all bucket duplicates except for the very first three we created.
> Delete all surplus bucket layers.
> Activate the third bucket layer.
Exact positioning
For exact positioning of the layer content, the Move Tool needs support. First of all, you can use the arrow keys. Please pay attention to the movement of the bucket at the bottom right.
> Press the right arrow and the up arrow several times.
The layer content can be moved in pixel steps by pressing an arrow key. If you want to make larger jumps, hold down the Shift key during the application.
> Press the left arrow and the down arrow with Shift several times.
The layer content is moved in 10-pixel steps using the Shift key.
In Photoshop, you can also use the guides and the ruler to help you position the layer. Cmd+R, for Ruler, shows the ruler.
> Press Cmd+R to hide and show the ruler.
In fact, the ruler plays a minor role in classical image editing. In web design, however, where the exact positioning of image parts is of greater importance, it does a good job.
We check the ruler’s units with a quick look at the Info palette.
> Info palette: Expand the units menu and finally close it again.
A click on the small arrow of the coordinates symbol of the Info palette expands the units menu. Here we can quickly change the unit of the ruler. We don’t have to do any manipulation in the Preferences.
> View / New Guide.
Guides can be created either by entering the desired values in the New Guide dialog or by virtually dragging them out of the rulers.
> Close the New Guide dialog.
> Drag the guide out of the vertical ruler.
If we carefully move the bucket to the vertical guide, we notice that the pixel edge docks to the guide with a small jerk.
> Move the bucket to the guide and let it dock.
> Open the View / Snap To menu.
The reason for this is that the guide is magnetic. We can enable or disable this property in the Snap To menu.
The small menu shows a few other aspects for which the Snap To function is available. But none of them are really useful. Only Snap to Grid and Snap to Slices make sense in web design at times.
If the Move Tool is activated, guides can be moved without any problems.
> Move Guides.
If page design is part of the task in Photoshop, as it is sometimes required in web design, it may be convenient to offset the zero origin.
> Offset the intersection point (zero points) of the two rulers.
Double-clicking the zero origin button resets it to the upper left corner of the document window.
> Reset zero origin.
If you want to delete a guide, simply drag it out of the document window with the Move tool.
> Remove guide with the Move Tool.
If you want to delete all guides in the document, select Clear Guides from the View menu.
> View / Clear Guides.
Align and Distribute
Sometimes it is necessary to align or evenly distribute layer contents. For these tasks, the Align and Distribute operations can be found in the Layer menu.
> Layer / Align and Distribute.
Since only one layer is active at the moment, we currently have no access to Align and Distribute.
> Close Layer menu.
> Activate all three bucket layers.
> Layer / open Align menu or Distribute menu.
Of course, using these operations via the menu items takes way too much time. And so we prefer to use the corresponding buttons of the Move Tool’s options bar instead.
> Close Layer menu.
> Options bar: Press Align right edges button.
> Cmd+Z.
> Options bar: Press Align top edges button.
If the layer contents are to be evenly distributed, the Distribute operations come into play.
> Options bar: Distribute horizontally button.
> Options bar: Expand Align&Distribute palette.
The Align&Distribute palette of the Move tool’s options bar provides an overview of all relevant operations. However, we will not delve into this topic here. I think it has become clear that Photoshop differs only marginally, if at all, in these points from the corresponding options of other programs.
Image montage
> Open Exercise file 8
Now let’s turn to a more important task in Photoshop: image montage. It is obvious that layers play an important role in this context.
Of course, we won’t be able to explore image montage in all its depths. But if we acquire a few basic techniques, we will have already gained a great deal. To this end, let’s go through an ideal workflow step by step.
The task is to place another roll in the empty space at the front right of the board.
Before the first steps in the image montage can be taken, the image editor must be clear about the essential aspects of the given lighting situation.
All parts added to the image must fit seamlessly into the given lighting situation in order to achieve a realistic-looking, plausible result. Image montage is about evoking total acceptance on the part of the viewer.
What can we say about the given lighting situation?
The first question we have to answer in the analysis concerns the position of the main light. The short shadows and the highlights sitting far above on the image objects, reveal that the main light comes almost vertically from above.
This has already given us two important pieces of information for the treatment of the added object and its immediate surroundings.
But the lighting situation is characterized by another aspect that we must not neglect in the image montage: The photographer has set a short, crisp effect light on the left. We can recognize the effect by the lightening of the left sides of the objects and by the yellow coloring, which tells us that a yellow foil was used.
The effect light is set at a very flat illumination angle and creates a local, almost spot-like, yellow brightening. In the left area of the image, the shadows of the main light are even partially eroded away. Towards the right, however, the effect diminishes rapidly.
All this information will guide us when mounting the added object at the appropriate position in the image.
For simplicity’s sake, I will now duplicate the roll in front and move it to the right. Since the subject clearly stands out from the background and should appear again against the same background, this is a case for the Quick Selection Tool or for the Object Selection Tool.
> Activate Object Selection Tool.
> Capture roll.
Let’s see if we need to improve the selection.
> Zoom in on the assembly zone.
> Improve the selection.
Using the already known shortcut for Layer via Copy I create a new layer with the duplicate of the roll.
> Layer via Copy via cmd+J.
> Enter layer name “roll”.
> Activate Move Tool temporarily by pressing the Cmd key.
> Move the roll layer to the right into the free zone.
> Zoom out a little via 1x cmd+minus.
I zoom out a bit so that we can judge the montage object in its environment. We realize: There is still a lot of work ahead of us if we want to achieve a halfway realistic result.
Drop shadow generation
First I take care of the drop shadow. A look at the shadows cast by comparable objects in the neighborhood gives me some initial clues as to how I should shape the shadow of our roll. The immediate model tells me that I have to set the shadow soft and short and that, with a small deviation to the left, it essentially falls to the front. And I can read off other shadow qualities, but all in order.
I’ll start with the shadow shape, that is, the extent of the shadow in its entirety. Since the shadow shape is derived from a three-dimensional object, applying the Drop Shadow layer style would not work. You remember …
> Double-click Layer Bar.
> Activate Drop Shadow and cancel.
A drop shadow, of course, wants to be brushed in all its specific aspects. We will not always find this as easy as in our example. The drop shadow of the bread roll will not be very spectacular and will hardly bring beads of sweat to the forehead of an experienced image editor. The drop shadow of a person walking or the shadow of a bicycle leaning against the wall, on the other hand, require much more intensive processing. Of course, the skills for creating complex shadows can only be acquired through practice. In the workshop we can at least get acquainted with the basics.
I’ll be brushing the shadow shape into a new, empty layer for reasons that are well known. Since I want the shadow to be below the roll, I’ll hold down the Cmd key while creating the new layer.
> Cmd-click on the button Create new layer.
> Enter layer name “shd”.
We certainly don’t need to name every layer we create, but at least the key layers should have a name. I will show you later how to take advantage of this moderate conscientiousness.
The qualities of the outline of the shadow shape are essentially determined by the qualities of the tool tip that I set for the Brush Tool.
> Activate Brush Tool, Tool tip round and soft, Size 100px, Hardness 0%.
I assume a standard round soft tip and set a diameter of about 100 pixels. With this I can achieve the specific fading of the shadow.
Now a shadow color has to be chosen. Shadows are usually not gray, in the sense of merely darkening. Shadow zones are almost always interwoven with reflections, which are sometimes more, sometimes less distinct and produce a specific hue.
In our case, the shadow is given a warm, brownish touch by reflections from the left side of the roll.
So we’ll choose an appropriate foreground color. I’ll specify a medium brown.
> Open Foreground Color Picker.
> approx. 35-70-85-45 and OK.
> Brush shadow shape.
The result is still far from being perceived as plausible. Basically, all I’ve done so far is create a blob of color. What is still missing is the darkening, which is the essential characteristic of a shadow. In other words, the color blob of the shadow layer must be blended with the pixels it is to darken. We achieve this goal by two interrelated actions: Darkening by choosing an appropriate blending mode and regulating the intensity by decreasing the opacity.
> Blending Mode: Multiply.
> Opacity: 75%.
Now, finally, the Blending Mode Multiply comes into practical use. Such and similar tasks are done with this special darkening mode.
A closer look at the present result shows that we have to add at least one more quality to our shadow if we want to achieve an acceptable look.
If we compare our shadow with other shadow zones given in the image, we notice that our shadow looks a bit flat. The other shadows are much more differentiated and thus more vivid than ours.
An essential quality that we still have to bring in is the so-called core shadow.
If we analyze the shadow zone of our model, we notice that the shadow on the lower right is darker and somewhat compact. This is due to the fact that the roll rests almost directly on the board. In the shadow zone on the left, where the contour of the roll has a certain distance to the base, the shadow is soft.
Findings like these may seem all too self-evident. But we should not disregard the fact that it is precisely a kind of self-evidence that we perceive as the hallmark of a realistic impression. It is exactly this self-evidentness that has to be created in the image montage.
> Click on the button Create new layer.
> Foreground color unchanged, Brush Tool Size 30px.
I keep the foreground color unchanged and reduce only the Brush Size. Reducing the diameter of the tool tip will give the brushstroke a more compact contour and that is exactly what we need here.
> Brush core shadow.
> Blending Mode: Multiply.
> Opacity: 60%.
Also fine-tune the core shadow using Multiply Mode and reducing the opacity.
> Fade out and fade in the shadow shape layer and the core shadow layer alternately.
If I temporarily hide one or the other shadow layer, you can clearly see the different tasks that the two shadow components perform.
> Zoom out to Fit on Screen.
Now let’s take a look at the entire scene to judge how the shadow is doing and to find out if anything else is needed to complete the image montage.
In fact, we also need to intervene in the tonal values and color values of the roll itself. Since the duplicate is more or less in the shadow of the first roll with regard to the effect light, the bright yellow spot on the left half of the roll is inappropriate. Consequently, we have to darken the roll there a bit and remove the yellow cast.
> Activate the roll layer.
I first take care of removing the yellow color cast. Since we don’t want to get lost in subtleties, I simply reach for the Sponge Tool and reduce the saturation a little in the affected area.
> Activate Sponge Tool, Size 400px, Mode Desaturate, Flow 10%.
I choose a very large, soft, round tool tip to avoid leaving unwanted brushstroke marks when brushing.
> Remove the yellow color cast by brushing repeatedly.
I do the shading again in a separate layer. This layer has to be positioned above the roll layer in the layer palette.
> Click on the button Create new layer.
Here, too, we do not have to strive for perfection in the workshop. I will just create a large, soft, dark spot. The foreground color is kept, the Brush Size is greatly increased.
> Foreground color unchanged, Brush Tool Size 400px.
> Set Brushstroke in the left half of the roll.
We again choose a suitable Blending Mode.
> Scroll in the Blending Mode menu.
Photoshop makes the selection easier with the life preview that scrolling in the Blending Mode menu provides. Trial and error is definitely an option here. Don’t settle for the first best blending result, always look at a few alternatives as well.
In the end I choose Multiply as Blending Mode again and adjust the intensity with the Opacity slider.
> Blending Mode: Multiply.
> Opacity: 60% for now.
The shading should of course be applied to the roll only. Other areas of the image must not be affected. It must therefore be restricted to the roll zone.
Clipping Mask
I could activate the bun selection for this, invert it, and delete the excess pixels of the shading layer. But I take a different approach.
It is much easier, faster and more flexible to create an intersection of the content of the shading layer and the roll layer. You may know the option to create clipping masks from Illustrator. This option also exists in Photoshop and its handling is very simple.
I move the cursor in the Layers palette to the line separating the two layers whose intersection I want to create and press the Option key.
> Move the cursor to the separating line and press the Option key.
The cursor turns into the clipping mask icon while the Option key is held down. The icon shows a thumbnail with a little bend arrow. You’ll see why in a moment.
> Create clipping mask by option-clicking the separator line.
If the separator line is clicked while holding down the Option key, the thumbnail of the layer above slides a bit to the right and a small arrow points down to the so-called base layer, which can be recognized by the now underlined layer name.
A look into the image confirms, the excess pixels have disappeared, the effect of the shadowing layer is only effective where there are pixels in the base layer. The clipping mask, or the intersection of the two layers, has been formed.
> Roll layer fade out and fade in again.
Now what are the advantages of this procedure compared to simply deleting the pixels that are not needed?
- The creation of a clipping mask is done by a single option-click – so it is much faster.
- The hidden content of the shading layer is retained and can be moved or re-displayed as needed.
Another option-click on the separator line of the two layers shows the entire content of the layer above again.
> Cancel the clipping mask by Option-clicking the separator line again.
Nothing has been lost.
Intersection is a convenient way to restrict layer contents and effects to a limited pixel zone, represented by the contents of the base layer. Incidentally, multiple layers can be included in the clipping mask to do their effect on the pixels of the base layer.
With this, we have learned a few first, basic techniques of image montage. Of course, there’s still a lot to discover, and we’ll take a closer look at some of it in the workshop.
Groups
We ended up needing three layers to reasonably recreate the lighting situation in our image montage. These three layers – Shadow Shape, Core Shadow and Shading – all relate to the roll layer. So all four layers belong together somehow.
If I want to move the roll in the image, the three shadow layers have to be moved along with it. To make sure that I don’t forget any layer, I create a group of the layers that belong together.
> Activate all four layers and group them via cmd+G.
> Expand the group in the palette.
Of course we know the group command from other programs: Cmd+G should be familiar.
If I want to move the roll, including its shadow layers, from now on I only have to move the group.
> Activate group.
> Activate Move Tool via Cmd-key temporarily and move the group to the free zone on the board to the left.
A new location usually requires a readjustment of the shadow or effect layers. It’s good that we have all the aspects that come into play in the image montage in the form of individual layers. This way we can adjust each aspect individually to the requirements of the new environment.
Since we sometimes can’t be sure that the position of an image element once defined will be the final one, we always keep all layers created in the image montage.
Merging layers that belong together, i.e. collapsing them into a single layer, is usually not a good idea.
> Expand the palette menu.
The only reason we might want to do this is revealed by looking at the file size. Because of the layers that have been added, the file size has now increased tremendously: It has de facto grown from a little over 8MB to a good 35MB.
Nevertheless, I can only warn against this. Please pay attention to what happens to the shadow when I merge the group.
> Merge Group.
A single layer is always in a single blending mode and with a single opacity setting. By merging, all adjustments would be lost, no multiply, no reduced opacity. This is of course not an option for us.
> Undo via 2 x cmd+Z so that the roll is back to the right.
The perfect Photoshop master contains all layers that are added during the image processing. A reduction of layers is only done in a few, very specific cases, so it should remain the exception.
Of course, the proliferation of layers in the Layers palette brings with it a certain amount of clutter. When 100 or more layers have accumulated in the Layers palette, it is easy to lose track of them all.
Once you have named at least the most important layers correctly, you can use a hidden function to find or activate a specific layer.
As I mentioned earlier, activating a specific layer by clicking the Move Tool will not be a viable option if you have a large collection of layers in the Layers palette.
> Cmd-ctrl-click on the bun in the image, keep context menu open.
The probability to find something here is high, as long as the most important layers are named correctly. If I did without giving the key layers meaningful names, the context menu will not have any useful entries: “Layer 1, Layer 2, Layer 3” ect. doesn’t tell you anything.
At the end of dealing with the basic montage techniques I would like to make two small remarks about the result.
Once the image montage is complete, you should take a step back and view the image with as little bias as possible. To clear the view, it is quite helpful to step away from the workplace for a moment, to go to the coffee kitchen or some other place.
Often it is only when you look at the result again that you realize what is still missing for the finishing touches. For my part, I find that the shading is still way too strong. A further reduction of the opacity can’t hurt here.
> Shading Layer, Opacity 20%.
But even if we had simulated the lighting situation perfectly with more time and greater dedication, our image montage would suffer from a fundamental flaw.
What the professional image editor would avoid at all costs is the use of a subject that is clearly recognizable as a clone. I said it before: in nature, absolute doubles do not exist. The obvious repetition of a motif indicates that the image has been edited.
If there is no independent motif that can be used inconspicuously, one is forced to resort to a clone. In this case, however, you eliminate all the distinctive features that could reveal the repetitive character. In our case, before creating the drop shadow, the image editor would have changed the shape of the clone, retouched the broken edge of the roll, and modified all the prominent pixels in general.
Layer masks
In addition to the clipping mask there is a completely different way of displaying sections of images. We will now deal with the powerful function of layer masks.
Image import
Let’s open exercise file 9 first.
> Open exercise file 9.
We want to insert the little starfish into our little beach scene, and to do this we need to bring the pixels from one document into the other.
It would be easy for us to create an exact selection of the motif. Nevertheless, we will do without it. A basic rule for image import is: preselection in the source image, fine selection in the target image.
Like all basic rules, this one should not be taken apodictically. In the majority of cases, however, adherence to this rule gives us the advantage of not being able to forget any image aspect of the source image that may be required. On the other hand, this procedure enables us to make the fine selection at the place of the event, i.e. where it has to work.
To create a rough preselection we use a typical preselection tool, namely the Lasso.
> Activate Lasso Tool.
> Lasso starfish generously, including shadow areas.
Copy&Paste
Copy&Paste offers us a possibility to transfer the selected motif into the target image.
> Cmd+C.
> Switch to the target image.
> Cmd+V.
To the familiar procedure I would like to make only two small remarks: If no selection is active in the image, Photoshop inserts the subject in the center of the image. If, on the other hand, a selection is active, the subject is placed selection-centered. You can take advantage of these two rules when positioning.
> Draw a small selection in the upper left corner of the image.
> Cmd+V.
> Delete layer 2 again.
The second specific when pasting a motif from the clipboard is that the pixels are inserted in the form of their own layer, which is of course extremely practical. “Layer 1” contains our starfish with environment.
Drag&Drop
Another way to transfer pixels from one document to another is via Drag&Drop.
> Delete Layer 1.
> Switch to the source image.
Since you often have to switch back and forth between several documents, let’s learn the shortcut for this right away. By pressing the keys Control and Tab (Windows: Strg+tab) we bring the opened images alternately to the view.
> Press ctrl+tab several times, at last exercise file 9.
We use the still existing preselection, activate the Move Tool and drag the motif in a first step to the name tab of the target file.
> Activate Move Tool.
> Drag the motif to the name tab of the target image and pause.
The target image is automatically brought to view. However, we must not release the keys, including the mouse button, too soon now, but still place the motif. Only when we have moved the cursor to the desired position in the image can the import process be completed.
> Place the motif in the gravel bed on the right.
Importing images via Drag&Drop is very convenient and goes quickly. Drag&Drop is therefore my preferred import method.
> Enter layer name “Starfish”.
To crop the motif, we quickly create a fine selection, e.g. with the Quick Selection Tool, and delete the background that was brought along and is obviously not needed here.
> Activate Quick Selection Tool.
> Select starfish.
We reverse the selection with the Inverse command and simply press the Delete key.
> Select / Inverse (cmd-shift+I).
> Press the delete key.
In fact, however, the image editor refrains from deleting image parts even in this case. Image parts that are not needed for the time being are only hidden, never deleted. This way you keep the possibility open to bring them out again if needed.
Even in our example this could make sense. Let’s go back two steps, so that the starfish is selected again.
> 2 x cmd+Z.
Since mounting the starfish requires an artificial drop shadow, the drop shadow we brought along could serve as a model for designing the shadow shape and other shadow qualities when the time comes.
So, don’t delete it, hide it, using a layer mask.
Creating a layer mask
Let’s have a look at the possibilities the Layer menu offers us for this.
> Open the Layer / Layer Mask menu.
Reveal all and Hide all are not important for us. We want to apply a layer mask to the already selected image.
If we want to keep the selected image in view, we use Reveal Selection.
> Layer / Layer Mask menu: Reveal Selection.
A look into the Layers palette reveals that a second thumbnail has been added to the layer thumbnail: the thumbnail of the layer mask. The layer mask ensures that the previously selected content remains visible and the unselected pixels of the layer become invisible.
What is a layer mask?
The appearance of the thumbnail already gives us a first hint about it. And when we option-click on the thumbnail to show the contents of the layer mask, it becomes fully clear what it is all about.
> Option-click Layer Mask Thumbnail.
A layer mask is an alpha channel. An alpha channel whose job is to mask image content in this one layer and nowhere else.
Let’s check this with a quick look into the Channels.
> Switch to the Channels palette.
If the layer with the layer mask is active, a new alpha channel will show up in the Channels: So a layer mask is basically an alpha channel.
> Return to the Layers palette.
By Option-clicking the mask thumbnail again, we hide the layer mask and show the image again.
Let’s take a closer look at the layer bar:
- Left, the layer thumbnail, which is the image.
- On the right, the mask thumbnail, which is the channel.
So the two thumbnails represent completely different facts. The white lines that frame the mask thumbnail indicate that the mask is now active and can be edited.
> Click on the layer thumbnail.
Clicking on the layer thumbnail activates the layer content, i.e. the pixels, which can now be edited in turn.
Another click on the mask thumbnail, and the mask can be edited. You might guess what I’m getting at …
The fourth entry on the checklist for quick troubleshooting is: Am I in the image or in the layer mask? Can the image content be edited or the mask content? The white border of the thumbnail shows it.
> Shift-click Mask Thumbnail.
The thumbnail is crossed out, and the mask is temporarily disabled. With another shift-click I return to the masked view.
> Shift-click mask thumbnail again.
Edit layer mask
Since the layer mask is an alpha channel, it can be edited like an alpha channel.
I make sure the mask is active, so I check that the mask thumbnail has a white border. For example, if I want to remove an arm of the starfish from the view, I reach for the Brush Tool and assign the clipping tip.
> Switch to the Brushes palette.
> Activate the clipping tip, size 200px, close the palette.
Remember: Applying black in the alpha channel causes the mask to close.
> Set foreground color to black via D key.
> Use a brushstroke to remove the top starfish arm.
If the arm is to be made visible again, I have to do nothing more than apply white.
> Swap the foreground and background colors via the X key.
> Bring the starfish arm back into view with a Brushstroke.
Since I can’t see the outline of the starfish through the closed mask, I don’t worry about the inaccuracy of the first steps. Once I have generously exposed the zone, I can bring the mask right up to the contour of the subject by closing it again.
> Swap foreground and background color via X key.
> Close the mask up to the starfish contour.
Link the layer mask
The small link icon between the layer thumbnail and the mask thumbnail tells us that the mask is linked to the layer content.
> Activate Move Tool and move the starfish layer.
The mask moves with the layer content as you move it.
By a simple click on the link icon we unchain it. The image and the mask can now be moved independently.
If I activate the layer thumbnail, the image can be moved within the mask.
> Activate layer thumbnail and move image.
> Cmd+Z.
If I activate the mask thumbnail, the mask can be moved across the image.
> Activate mask thumbnail and move mask.
If the layer mask is no longer needed, it can be hidden with a Shift-click, as I said. If you want to delete it completely, drag the layer mask thumbnail to the trash can icon in the footer of the Layers palette.
> Drag the mask thumbnail onto the trash can.
Photoshop asks me three questions to confirm the deletion.
- Should the mask be applied to the pixels. Any pixels currently hidden by the mask will be lost forever.
- Should the mask be deleted without application. The hidden pixels will reappear. The initial state is restored.
- The option to cancel poses the question whether I really want to delete the mask, or whether I rather want to hide it and thus keep it in the back.
We choose Delete, because we want to bring all imported pixels back to view.
> Delete Mask.
Finally, I’d like to point out two more ways to create layer masks. The way over the Layer Menu is too long for us.
Paste into
Option 1 uses a selection active in the image to mask the subject pasted from the clipboard.
> Draw any selection with the lasso.
> Edit / Paste Special: Paste into (cmd-option-shift+V).
Paste into places the pixels from the clipboard into the selection, which in turn is converted into a layer mask, as a glance at the Layers palette proves.
Since the paste is usually to be followed by an exact positioning, the thumbnails are not linked at first.
> Move the layer content a little with the Move Tool.
> Activate link.
> Move layer content and mask together.
> Delete layer.
Add layer mask
Option 2 to create a layer mask is quick and convenient and therefore the way we mostly go in practice.
After we have created a selection of the subject we want to keep in view, we just have to press the Add layer mask button at the bottom of the Layers palette and the goal is achieved.
> Activate the Quick Selection Tool.
> Select starfish.
> Press the Add layer mask button.
I think from the very first exposure to layer masks, it becomes clear the importance of this technique in the context of image montage. In fact, working with layer masks is the key to image montage and, moreover, an indispensable feature in building the perfect Photoshop master. What I hide today, I can bring out tomorrow. Nothing is deleted, everything remains available.
Before we move on to the next big thing, let’s tidy up our practice document a bit. A bit of order can’t hurt.
We’ll delete all the layers and keep only the background layer. And we’ll take a look at the channels. Only the RGB channel, the color channels and our bucket alpha channels should be visible there. If there are other channels, we delete them.
> Activate and delete all layers.
> Delete surplus channels.
Paths
So far, we’ve encountered two worlds in our tour of Photoshop: images and masks. Images are layers, masks are ultimately alpha channels. One is found in the Layers palette, the other in the Channels palette.
Now let’s open the door to another world in Photoshop – the world of paths.
> Open Paths palette.
Along with layers and channels, paths are the third element in the bundle of main palettes.
At this point, the Paths palette is still empty. Let’s create a first path right away. But before we do that, I want to look at the subject from its general side.
What is a path?
We know paths from relevant programs like Illustrator. They also play an important role in InDesign. And 3D modeling is virtually based on paths. All these applications operate with vector data, i.e. with paths.
Now we have learned that Photoshop is not a vector-oriented program, but a pixel-oriented one. Although paths cannot show their strengths in pixel environment, working with paths is also of great importance in Photoshop.
In fact, we’ve already dealt with paths in the workshop, in the form of very specific vector outline objects. Recall what I said about type: The shape of a letter consists of so-called Bézier curves, in another word: paths.
Paths are precisely defined curves consisting of modelable curve segments and anchor points. Some of you will have already learned the basics of path creation, for example in your dealings with Illustrator. Since we’ll be using these basic techniques in Photoshop as well, and I can’t assume that you’re all on the same page with this topic, we’ll also learn the essentials in the Photoshop Basics workshop.
Creating a Path
Path creation starts with choosing an appropriate tool.
> Open the Paths drawer in the Toolbox.
We can choose from a number of specific path tools in the toolbox or resort to shape tools for creating vector objects.
> Expand the Shape drawer in the toolbox.
Since we want to learn the basics, we first select the classic Pen Tool.
> Activate Pen Tool.
We make sure by looking at the options bar that the path creation mode is activated and that we are not creating a vector shape using the Pen Tool.
> Open the Tool Mode menu and select Path if necessary.
I will now create a path along the outline of the bucket. I think learning by doing is the best way to acquire the necessary skills for path creation.
> Zoom in on the bucket.
> Set the first anchor point.
As soon as the first anchor point is set, a so-called Work Path appears in the Paths palette. The Work Path is only for path creation, so it is not a real path yet.
I continue to set anchor points.
> Set three to four more anchor points along the outline of the bucket.
The curve segments connecting the anchor points finally form the path. However, there is no question of curves here. Since I created the anchor points by clicking on them, they exist as corner points and the curve segments as straight lines.
If I want to create curves, I have to proceed differently.
I delete the path and start again from the beginning.
> Delete path by pressing the delete key twice.
> Set first anchor point.
The first anchor point is created in the usual way by a click.
The second anchor point should now become a smooth point, and not a corner point again. For this I have to adjust my technique: I click and drag the newly set second anchor point at the same time.
> Set smooth point to 9 o’clock by clicking and dragging.
As you can see, this creates two direction lines with direction points at each end. The direction lines and the direction points are used to modify the curve.
Changing the length and orientation of the direction lines affects the shape of the curve located between the first and second anchor points.
I set other smooth points in the same way – always by clicking and dragging. I try to make the curve segments fit the contour of the subject as exactly as possible. One of the tricks is to make the line formed by the two direction lines tangential to the contour of the subject.
> Set smooth point to 6 o’clock by clicking and dragging.
> Set smooth point at 4 o’clock by clicking and dragging.
The curve between the last two anchor points set doesn’t quite want to follow the contour of the bucket. In this case, I probably chose the distance between the two anchor points too small – their direction lines get in each other’s way. In fact, there are many reasons that make it necessary to rework a path. Fortunately, one can be easily accomplished.
Changing anchor points and curve segments requires a tool change. I reach for the Direct Selection Tool because only with this can a single anchor point be activated for editing. And only with this can the direction points on the direction lines be touched in order to modify the curve.
> Activate Direct Selection Tool.
Of course, we don’t actually make the tool change, but again use a shortcut to temporarily activate the Direct Selection Tool. We always stay with the Pen Tool and get the Direct Selection Tool by pressing the Cmd key.
> Activate Pen Tool via P key.
> Press Direct Selection Tool via Cmd key.
Now the direction points can be touched and moved. And also the anchor points can be activated and moved with the Direct Selection Tool.
> Move direction points.
> Move anchor points.
By the way: Active anchor points appear filled, inactive anchor points appear empty. Active anchor points can also be moved in tiny increments using the arrow keys.
> Move anchor point using the arrow keys.
> Perfect the path with Direct Selection Tool.
When I release the Cmd key, I have the Pen Tool in my hand again and can immediately continue with the path creation. Clicking on the last set anchor point activates it and we can continue the path creation.
> Tie to the open path.
> Set smooth point to 3 o’clock by clicking and dragging.
If I want to insert an anchor point into the created path, I have to change tools again.
> Open the Paths drawer in the toolbox.
I would have to activate the Add Anchor Point tool for this. If, on the contrary, an anchor point is to be removed from the path, the Delete Anchor Point Tool is a good choice.
But just like the Direct Selection Tool, both of these tools can be activated temporarily. And the small Auto Add/Delete checkbox of the Pen Tool’s options bar ensures that you don’t even have to press a keyboard shortcut to do this.
> Move the cursor slowly towards a path segment at about 8 o’clock.
When the Pen Tool is moved towards a path segment, it automatically turns into the Add Anchor Point tool. And with a single click, the new anchor point is added.
> Add Anchor Point.
And vice versa, if an anchor point is to be deleted, move the cursor towards the point to be deleted. The Pen Tool automatically turns into the Delete Anchor Point Tool. One click is enough to remove the anchor point from the path.
> Delete the same anchor point again.
> Open the Paths drawer in the toolbox.
In the Paths drawer you will find a few more useful tools. Please familiarize yourself with the Freeform Pen Tool, which allows you to draw freely, and the Curvature Pen Tool, which creates smooth curve segments. However, we need to take a closer look at the much more important Convert Point Tool.
As the name of the tool suggests, it is used to convert a corner point to a smooth point or a smooth point to a corner point. We will see what this is good for in a moment. Since this tool can also be activated temporarily via a key command, there is still no reason for us to put the classic Pen Tool out of our hands.
> Close the Paths drawer in the Toolbox.
To temporarily activate the Convert Point Tool, all you have to do is press the Option key. If you move the Pen Tool cursor close to a smooth point while holding down the Option key, the Convert Point Tool cursor icon will appear. And with a click on the smooth point it changes into a corner point.
> Convert the smooth point at 9 o’clock via Pen Tool Option-click into a corner point.
And with exactly the same procedure, the opposite effect can be triggered, i.e. converting a corner point into a smooth point.
> Convert the corner point at 9 o’clock back to a smooth point via Pen Tool Option-click.
I continue the path creation. As usual, I link to the open path by clicking its last anchor point.
> Tie to the open path.
> Set smooth point by clicking and dragging on the intersection of the two contour lines of the bucket.
The intersection of the two contour lines of the bucket presents a bit of a challenge for path creation: Obviously, a corner point is required here. The path must have a hard bend at this point. But the path segment between the penultimate point and this corner point must have the shape of a curve. So we would have to set a corner point here that is a smooth point. How do we do that?
Again, the Convert Point tool helps us here. I press the Option key to activate it, grab the direction point of the direction line responsible for the further course of the path and bend the direction line.
> Bend the direction line using the Convert Point Tool.
It is important to make sure that the bent direction line points exactly in the direction in which the path is to continue. With this, I created the hybrid anchor point I needed.
The last anchor points on the way back to the starting point are quickly set.
> Set the remaining anchor points. Pause just before closing the path.
> Hover the cursor over the starting point of the path.
The small ring near the cursor indicates that I am about to close the path. When the starting point of the path is clicked, the path creation is complete.
In fact, we are still dealing with a temporary Work Path. If the drawn path is to be preserved in its current form, I still have to convert it into a real path. This is done by double-clicking on the path bar and assigning a meaningful path name.
> Double click path bar, name entry “bucket”.
If I want to draw a second path, I can deactivate the just finished path by clicking somewhere in the empty area of the Paths palette and starting again.
> Deactivate bucket path.
> Set a first anchor point somewhere in the image.
A new Work Path appears. The rest of the procedure is familiar.
> Delete the new work path using the delete key.
The conserved bucket path can be reactivated at a later time if necessary by clicking on the corresponding path bar.
> Activate bucket path.
If I also want to view the anchor points on the path line in order to modify them, I activate the Direct Selection Tool and click the path line in the image. And the modification can start.
> Show anchor points via Direct Selection Tool click.
Now it’s time to ask what paths are actually needed for in Photoshop – a decidedly pixel-oriented program.
Create path selection
As strange as it may sound, a first important task done using paths is to create selections. We can, starting from any closed path, easily create a selection. We can thus think of paths as stored selections.
And we already know the method how to convert a path into a selection: We click the path thumbnail while holding down the Cmd key.
> Create path selection by Cmd-clicking the path thumbnail.
Using paths to select parts of an image seems awkward at first. However, as soon as we have become acquainted with the genuine qualities of a path selection, we will no longer want to do without this option.
Let’s save the path selection as an alpha channel for comparison purposes. We switch to the Channels palette and save the selection in the familiar way.
> Switch to the Channels palette.
> Select / Save Selection: Entry “Bucket_P”, OK.
We cancel the selection with Cmd+D and zoom in to the bucket area.
> Cmd+D and zoom in.
What we see here is a very smooth, sleek, compact, hard selection outline that is best suited for selecting appropriate subjects. It’s the exactness and smooth curve that makes path selections so special.
Let’s compare this with the other saved selections, each of which represents a different selection technique.
> Activate Bucket_L.
With the lasso you usually create only rough preselections.
> Activate bucket_Q.
> Activate bucket_O.
The Quick Selection Tool and the Object Selection Tool are usually used to create relatively good, natural selections of objects that are to be processed on the spot.
> Activate Bucket_B.
The Brush Tool provides precise selections of motifs that are to be edited or transposed in place. The choice of tool tip determines the qualities of the selection outline. This makes the Brush Tool our most flexible clipping tool.
> Activate Bucket_P.
The path provides an idealized selection, so to speak. Paths are used for selection creation when a subject, which itself has a hard, smooth outline, is to be selected to be mounted on a neutral or artificial background.
Think, for example, of the packshots in grocery store flyers or the product that is clipped, i.e., shown against a neutral background, on an online retailer’s product page. Most of these objects were captured in the PSD master, i.e. the original working file, with a clipping path. The clipping path guarantees perfect subject selection.
Painting by paths
Another way to use paths in Photoshop is to facilitate line drawing and painting. A path can be used in certain ways as a preliminary drawing for creating a complex line.
Let’s see how this works with a concrete example.
We switch to the Layers palette and create a new, empty layer there.
> Switch to the Layers palette and Create a new layer.
After all, we don’t want to paint into the background layer. We return to the Paths palette, deactivate the bucket path there by clicking on the empty area of the palette to be able to start with a new Work Path.
With the Pen Tool we now draw a completely arbitrary, complex path, which we finally close by clicking on the starting point of the path creation.
> Switch to the Paths palette, deactivate the current path.
> Activate Pen Tool if necessary and draw a complex path.
Once the path is finished, we reach for the Brush Tool and equip it with a round, hard tool tip. The current foreground color should be fine for us.
> Activate Brush Tool, round hard, Size approx. 100px.
Once we have done this preliminary work, we only have to let the just defined brush tool run along the path. To do this, we open the Palette menu and select – how could it be otherwise – the entry Stroke Path.
> Open the Palette menu and select Stroke Path.
In the small dialog you can’t do much more than select a tool to apply to the path contour.
> Stroke Path dialog: Expand Tools menu.
A look into the menu shows that partly completely different tools can be defined here. We could erase along the path, retouch, blur, sharpen, etc. For demonstration purposes, we chose to use the Brush tool.
> Stroke Path dialog: Select Brush and OK.
Once we’ve given OK, the Brush Tool will race along the defined path and nothing can make it stray.
The advantages of working with paths as a preliminary drawing are obvious:
- We can draw the path at our leisure and modify it until it meets our needs.
- This allows us to achieve a precision that is not possible when drawing with the free hand.
- Furthermore, the line remains saved as a path and can be precisely corrected at a later time or used for any other operation.
Of course, the path creation itself has to be considered a small disadvantage. Path creation can be laborious and takes a certain amount of time. So we’re not going to create every line we want to brush in Photoshop through the detour of path creation.
Let’s delete the layer and the Work Path so they don’t irritate us in the next steps.
> Delete Work Path.
> Switch to the Layers palette, delete layer.
> Switch back to the Paths palette.
Clipping Path
I would like to address a third possible application of paths only briefly in the introductory workshop: paths can be used as so-called clipping paths for exporting precisely cut out parts of images to other programs.
If I want to show our little bucket cropped, i.e. in its own form without any background, in Illustrator or InDesign, I can convert the path we used to capture the object into a clipping path and export the file as EPS.
> Enable Bucket Path.
> Expand the palette menu and select Clipping Path.
The small dialog basically only specifies the path to be converted to a clipping path. We can safely ignore the flatness, i.e. the curve approximation.
> Clipping Path Dialog: Path “Bucket” and OK.
Once we have made our choice, the first step is done. The bold font of the path name indicates that this path is the clipping path, the contents of which will then be visible without an environment after loading the image, for example in Illustrator. Please try this out for yourself when you get a chance away from the workshop.
Shapes
If you are familiar with Illustrator, you know that we are not only dealing with paths as lines, but that so-called vector objects also play an important role. The red circle, the blue rectangle, the black star. A vector object is a path whose surface is filled with color. And it will not surprise us that we can handle something very similar in Photoshop.
We can find the tools that allow us to create such vector objects in Photoshop in the drawer just below the drawer that contains the path selection tools.
> Expand Shape Tools Drawer.
The tools listed here are reminiscent of Illustrator’s corresponding tools, and work quite the same way in use. However, we’re actually dealing with something quite different here in Photoshop, as we’ll see in a moment.
We’ll disable our bucket path and go to the Ellipse tool.
> Disable Bucket Path.
> Activate Ellipse Tool.
Now, before we use this to draw a circle, we need to make sure of three parameters:
First, in the tool’s options bar, we need to make sure we are actually creating a shape layer and not just a path with no fill. The Tool Mode must be set to Shape.
> Options bar: Open the menu and change it to Shape if necessary.
Secondly, we need to define a fill color. We use the Color Picker of the options bar.
> Options bar: Open Fill Color Picker and select any color.
And third, we need to determine whether the contour line should also receive a color fill or whether it should remain unfilled.
> Options Bar: Open Stroke Color Picker and set it to No Color.
Since we want to do without a contour line, we select “No Color” in the Stroke Color Picker. Otherwise, of course, we would have had to specify a contour thickness.
> Draw a circle.
As usual, we draw a circle in the image.
Vector vs. Pixel
As expected, the shape has the appearance of a vector object: path with color fill. But what exactly is a vector object in Photoshop, a decidedly pixel-oriented program? Zooming in on the outline of the shape tells us.
> Zooming in on the circle line.
Since color in Photoshop is a pixel quality, it can only be expressed in pixels. We can clearly see that the path line here is not a true boundary of the color fill at all. Rather, the path line acts as a clipping of a color area that consists of pixels.
A vector object in Photoshop thus consists of two components: a colored pixel area and a path that crops that area. This fact is expressed equally in the Paths palette and the Layers palette.
The Paths palette contains the clipping path, named “Ellipse 1 Shape Path”.
> Switch to the Layers palette.
And the Layers palette contains the “Ellipse 1” layer with a color fill clipped from this path.
So, in a strict sense, no real vector objects exist in Photoshop. We should therefore better speak of shape layers.
The concept of shape layers can also be conveyed in other words: A shape layer is a fill layer with a vector mask.
I do not want to expand this topic too much. At this point, therefore, just a note that we can also create both – the fill layers and the vector masks – manually in Photoshop.
> Open the Layer menu: New Fill Layer and Vector Mask.
I do have to make one comment of a general nature about the shape layers, though. We might think of doing without vector objects in Photoshop. We can also define the shape of a color area using a selection. Or: The content of a fill layer can be clipped with a normal layer mask. In fact, we use both of these options in many cases.
However, the decisive argument for the specific use of paths and shape layers is something that cannot otherwise be achieved in the pixel world: absolute precision and free scalability. Nothing is more exact than a path. And a path, respectively a vector object, can be enlarged, reduced again and enlarged again etc. without losses.
The vector shape always remains the same during all processes and in all image sizes. Pixels, on the other hand, must be recalculated for each scaling operation, which sometimes quickly leads to unacceptable results.
Shape layers behave in a scale-neutral manner and can be edited in Photoshop in much the same way as we are used to in Illustrator. A look at the Options bar and a look at the Properties palette, which was automatically expanded when the shape was created, introduces us to the relevant tools.
Properties palette:
- We can change the dimensions and the position. We can modify the color fill afterwards, set a line width and a line type.
- We can specify the position of the line fill: Center, Inside or Outside.
- And here, of course, we find the Pathfinder with which we can perform path operations such as combination, subtraction, intersection and remove overlapping areas.
Of course, the path of the shape layer can also be edited with the normal path tools.
And what’s more, the concept of shape layers in Photoshop opens the door for us to use graphic elements of any kind. We can place illustrations from Illustrator into Photoshop. We can import logos. We can insert pictograms. There is no obstacle to adding any vector object in Photoshop.
> Zoom out via cmd+0.
> Activate Custom Shape Tool.
> Options bar: Expand Shape palette.
Using the Custom Shape tool, we can choose from a set of standard pictograms.
> Select any pictogram and create it in the image.
Of course, we don’t have to be satisfied with this manageable set. We can create our own vector shapes in Photoshop, paste vector shapes from Illustrator via copy/paste, or import additional vector shapes into the Shape palette where they will be available for future use.
> Options bar: Expand Shape Palette.
> Expand Palette menu: Hint to Import Shapes and collapse again.
Paths and path operations are indispensable in image processing. Numerous techniques also rely on the qualities of the vector world in Photoshop, and numerous image editing tasks cannot be solved without paths.
I’ll come back to paths and shapes in the Photoshop Advanced Workshop when we look at precise illustration techniques. For now, let’s leave it at that.
Format
Format and cropping of an image belong to the most natural things you can think of in image processing. Nevertheless, I would like to say a few words about this as well.
> Open exercise file 10.
Canvas Size
The dimensions of the image are identical to those of the canvas. The image fills the canvas completely. This is the situation we usually face.
If you want to add to the left, right, top or bottom of the image, you have to increase the size of the canvas first. We do this in the Canvas Size dialog.
> Open Image / Canvas Size.
Since this dialog is useful from time to time, let’s remember the key shortcut, which is: Cmd-option+C. The C stands for Canvas, of course.
We want to extend the image downwards by 50 mm. To achieve this, we add the desired value to the current value in the Height input field. We leave the calculation to Photoshop.
> Height input field: “423.33+50”.
In the Anchor Matrix we determine in which direction the image will be extended. To extend the canvas downward, we place the anchor in the middle field of the top row.
> Place the anchor in the middle, upper field.
Before we give OK, we have to decide with which color the added area should be filled. We decide for a white fill.
> Canvas Extension Color: White and OK.
Crop
Much more often than extending the image, it is necessary to crop it. Edge areas of a photo that have no use should sometimes be removed before starting the actual image processing.
With the help of a suitable selection, cropping of the image can be performed in a simple way. We use the Rectangular Marquee Tool, draw a selection and use it to capture the area of the image that should be preserved.
> Activate Rectangular Marquee Tool, Feather 0px.
> Capture the original image area.
Once that is done, all we have to do is select the Crop command of the Image menu.
> Image / Crop.
However, cropping is only appropriate when we can be sure that the edge areas are not needed and the resulting reduced file size is somewhat significant in the workflow. So images are not cropped in principle or brought to format in image processing, but always only according to the requirements.
And at this point, a professional tip that is equally important for photographers and image editors: Since the graphic designer determines the final image section, she needs some leeway in handling the images. She needs images with a bleed. The technical term bleed means that the motifs must not be cropped too tightly, but must have a certain overhang in the marginal area.
The photographer must therefore not choose the image crop too precisely, but must create this leeway by making a moderate addition in the marginal area. And the image editor must also not carry out any premature cropping. Once again: The final crop is only determined by the graphic artist.
Trim
I would like to briefly point out the difference between the Crop and Trim functions. Both functions are used to remove unwanted edge zones, but they aim at different aspects.
> Unselect via cmd+D.
Crop, i.e. the classic cropping or clipping, is a thoroughly manual process. We select an image section, as just demonstrated, and crop it by applying the Crop command. All parts of the image outside the selection are removed.
Trimming an image is about removing uniform areas of color or transparent areas around the edges. The process is semi-automatic. Let’s enlarge the canvas again and have a quick look at it.
> Image / Canvas Size: 500 x 400mm, Anchor center/center and OK.
Our image now has a monochrome border zone, as it is created during scanning. In order not to lose any pixels in the border area of the motif during such processes, one selects the section somewhat larger as a precaution. The scan border can then be conveniently trimmed in Photoshop.
Open > Image / Trim.
First, you select a zone that has the pixel color you want to remove. Since the white border encloses the entire subject, we don’t have to worry about this. Top Left Pixel Color is just as suitable for this as Bottom Right Pixel Color.
Now we have to determine the zone itself that should be removed. For example, if I want to remove only the white pixels in the right border area, the other zones must be deactivated.
> Based On: Top Left Pixel Color, Trim Away: Uncheck Top, Bottom, Left and OK.
Crop Tool
With the Crop Tool Photoshop offers a third possibility to crop images.
> Activate Crop Tool.
Its use is basically as simple as can be, but the options the tool opens up are many.
Crop
When the Crop Tool is activated, a cropping frame appears in the image, providing a preview of the expected result. The grid and shading zone can be modified in the Overlay Options and the Additional Options.
> Expand and collapse the Additional Options menu.
We are content with the default settings and turn to more interesting parameters.
> Expand the Format menu.
In a first step we set an aspect ratio or a target size. The Format menu contains a number of presets concerning these two parameters. Here we can find typical photo formats as well as typical web formats. And with Original Ratio we keep the original aspect ratio of the image.
> Format menu: Original Ratio.
If we want to freely choose a specific aspect ratio, we switch to Ratio.
> Format Menu: Ratio.
We enter the values of the aspect ratio into the numeric input fields and first bring the cropping frame to the desired size. In a second step, we define the image section.
> W x H Enter 5:3 and fit the cropping frame into the subject.
If exact target values are to be achieved, we select W x H x Resolution as the starting point in the Format menu.
> Format menu: W x H x Resolution.
> W x H input 100 mm x 90 mm.
> Adjust the image section and move it a little manually.
To define the exact target values, it is important to specify the unit in addition to the value. If we do not enter a unit in the input fields, Photoshop will use the last unit of measurement defined.
We could now also enter a value for the resolution to set a target resolution, e.g. 300 dpi for print output. However, I do not recommend setting the image resolution during the cropping process. Changing the image resolution should be done in the Image Size dialog with its elaborate controls. So we leave the Resolution field blank.
Before we apply the cropping, we still have to decide what to do with the removed parts of the image in the border area. An important feature of the crop tool is that the removed border areas do not have to be deleted. Photoshop virtually remembers the original format of the image and the removed content. If I want to use this feature, the Delete Cropped Pixels checkbox in the Options bar must not be checked, of course.
> Uncheck Delete Cropped Pixels
Basically, we can now give our OK to cropping. However, I would like to point out another important feature of the Crop tool, the ability to straighten the image.
Straighten
To normalize the camera tilt, i.e. to align the horizon in the image absolutely horizontally, all you have to do is press the Straighten button in the options bar and use the Straighten tool activated by this to capture the line that is to be normalized.
> Activate Straighten Button.
In our image, normalization of the horizon line is not necessary. On the contrary, we can use the tool to draw in a camera tilt afterwards.
> Draw the line at the roof edge.
If we place the line at the upper edge of the roof, the tilt effect will immediately appear in the preview. The image gets a dramatic expression due to the slight tilt. Rotating the image can also be done manually.
> Rotate the image in the opposite direction by dragging the cropping frame.
If we are satisfied with the preview, we only have to press the Enter key and the process of cropping and straightening is completed.
> Finish the cropping process with OK.
A look into the Layers palette shows that the background layer has been converted into a real layer with the name „Layer 0“. This is quite correct and is not a bad thing. The reason is that we did not delete the border zones, but kept them in the background. As a result, the motif dimensions and the canvas are no longer congruent.
If we activate the Move Tool to move the image a little, we immediately see how this is meant and what possibilities it gives us.
> Activate Move Tool and move the image.
We can use this option to make an adjustment to the section at any later time.
Cropping and straightening are usually done before the actual image processing begins, but always with the desired final format in mind, including bleed.
Let’s restore the original state of the image.
> History palette, click on the first snapshot.