I find it helpful to have a shortcuts reference table by my side. (Eventually I'll commit these to memory, if I use them often enough.)
Note: to cycle through individual members of a tool set, hold down the Shift key while pressing the tool's shortcut key.
|Paint bucket / Gradient||G|
|Blur / Smudge||R|
|Dodge / Burn / Sponge||O|
|Eyedropper / Colour sampler / Measure||I|
|Levels||Ctrl+L||To work on active image layer or Background.|
|Curves||Ctrl+M||To work on active image layer or Background.|
|Auto Levels||Ctrl+Shift+L||Applies to active layer or Background.|
|Auto Contrast||Alt+Shift+Ctrl+L||Applies to active layer or Background.|
|Feather selection||Ctrl+Alt+D||Opens dialog box where Radius can be specified.|
|Adding to a selection||Shift-click||When working with selection tools.|
|Subtracting from a selection||Alt-click||When working with selection tools.|
|Getting the intersection of two selections||Shift+Alt-drag with selection tool||When dragging selection tool over an existing selection.|
|Fill selection with foreground colour||Alt+Backspace|
|Fill selection with background colour||Ctrl+Backspace|
|Display Levels palette||F7|
|Display Colour palette||F6|
|Show / hide Info palette||F8|
|Show / hide Rulers||Ctrl+R|
|Fit on screen||Ctrl+0|
Apart from the paint brush, the shape tools appear to be the most basic and straightforward to use when we quickly want to throw together some simple graphic or artwork. After all, we all had some experience with the Windows Paint program and it was easy enough. Working with shapes in Photoshop is not that instinctive, though. If we set out to work with the default settings, the first thing we notice - to our amazement - is, that with almost every move we have inadvertently created a new layer. With the added complexity of blending modes, tool and shape area options, things can get even more confusing. Press a key here and there and the program switches in and out of modes that do things to the image we never intended. Total despair ensues as our work ends up in a mess. To keep my sanity, I noted down a few things I learned from books and by trial and error, so that I can get a better picture of how these tools work. Hopefully, others will find it also useful.
Shapes in Photoshop are objects that can be selected, moved, resized, and have properties (eg. fill colour), that can be edited. They are resolution independent vector graphics (as opposed to bitmaps). However, it is also possible to draw rasterised shapes on an existing layer (but not on the Background). These shapes are permanently etched into the image, and cannot be selected and edited later.
Paths are the outlines of shapes. When a shape is drawn, its outline (the so called, layer clipping path) is stored separately on the Paths palette. The term layer clipping path refers to the fact that the outline forms a boundary around the fill colour (and pattern) of the shape. If you remove the outline, the fill 'spills over' and covers the entire layer.
Another way to create a path is by drawing it with the Pen tool. Such a path is also stored on the Paths palette and is given the name Work Path by Photoshop. There can only be one Work Path, so if you don't want to overwrite it, you need to save it under a different name before drawing your next path.
As it follows from the above, the Shape and Pen tools (shortcuts: U and P) have somewhat overlapping functionalities. Importantly, you either create
a new shape layer or a Work Path with them. You would chose to create a Work Path, if you intend to end up with an outline, only - possibly in order to
convert it into a selection in a later step. You'd create a shape layer, when you want to fill an area on the image with some colour. The
Create new shape layer and
Create new work path options (first group of buttons
on the options bar) are available for both the Shape and Pen tools, but they work slightly differently. This is how I would use them:
Create new shape layermode.
Create new shape layermode.
Create new work pathmode.
Create new work pathmode.
Create filled regionmode. (Imitates how very simple Paint programs work.)
Create new work pathmode can be edited later to create a more irregular shape. This can be done by using some kind of transformation (eg. Free Transform >> Skew) and/or by adding/deleting/repositioning anchor points.
A path doesn't have to be closed, even if it was drawn with the
Create new shape layer option. But, curiously, the fill occupies an
area, which is the same shape as that of the closed path.
When you draw overlapping outlines, the effects of the shape area options (eg. intersection) don't show up until you fill the path with the foreground colour or convert the path into a selection.
When you click on an existing shape layer on the Layers palette, it immediately goes into edit mode. This means, that you can draw additional shapes
onto this layer. How they affect other shapes on the same layer, depends on which one of the shape area option buttons (eg.
Subtract from shape
area (-)) is enabled. (This is only of interest, if the shapes overlap.) Caution: if you press Enter, Esc, or click on the layer clipping path
thumbnail, the layer goes out of edit mode, and as you draw your next shape you end up creating a new shape layer.
When you have a path selected on the Paths palette and you go back to the Layers palette and select a shape layer, its outline will not show (i.e. its clipping path will not be selected). You need to click on the layer clipping path thumbnail to select the clipping path (and let it show up).
When drawing shapes, hold down the Shift key to constrain proportions of the object (eg. to draw a square). Hold down the Spacebar to reposition the object while drawing. Hold down the Alt key before starting to draw to draw from the center of the shape.
When working with existing shapes and paths with the Shape tool, hold down the Ctrl key when clicking on a shape or path to select it. (The cursor turns into a black arrow.) After this, hold down the Shift key and click on other shapes or paths to add to the set of selected shapes and paths. Once a shape or path is selected, it can be moved simply by dragging. You can clone a path by selecting it, then holding down both the Ctrl and Alt keys and dragging.
When you create a new path with the Pen tool in
Create new work path mode, or edit an existing path, the following manipulations are possible:
Add new anchor points by clicking and - optionally - dragging. (If the
Rubber Band option is checked, Photoshop shows you where the next line segment will
fall before you put down the next anchor point.)
There are two types of anchor points; curve points and corner points. Curve points have control handles. If you simply click, you add a
corner point. If you click-and-drag, you add a curve point.
A curve point can be changed
into a corner point by clicking on it while holding down the Alt key (the cursor turns into a ^ shape). The reverse is possible by
clicking and dragging while holding down the Alt key. Manipulate a control handle with the Alt key held down.
You can insert an anchor point between two existing anchor points by clicking on the line that connects them.
Delete an existing anchor point - except the first and last point - by clicking on it. If you click on the last anchor point (the current end-point), the program simply goes into 'ready to accept new anchor points' mode. If you click on the first anchor point.... see next.
Finish drawing a closed outline by clicking on the first anchor point (the start-point). The program connects the last anchor point and the first, thus completing the path. Note: it is perfectly legitimate to leave a path open (i.e. the first and last anchor points are not connected).
Hold down the Ctrl key (the cursor turns into a white arrow) and click on an anchor point to select it. Reposition it by dragging (while still holding down the Ctrl key). Note: the same can be achieved in two steps by first selecting the Direct Selection Tool (shortcut: A) from the toolbox and then clicking on the anchor point. To select multiple anchor points, hold down the Shift key while the white arrow pointer is active. To unselect, click on a selected point while the white arrow pointer is active and the Shift key is held down. (You might have to click twice - a Photoshop bug?) To select an entire path (all anchor points) all at once, you need to use the Path Component Selection Tool (shortcut: A) - a black arrow.
The Path Component Selection Tool (black arrow) can be used to select, transform, combine, and align paths (outlines). When working with the Shape tool, the
Path Component Selection Tool can be accessed by clicking on the path while the Ctrl key is held down.
Show Bounding Box has to be
checked to be able to use transformations on the path.
Clicking on a path tab on the Paths palette while holding down the Ctrl key will load that path (including all sub-paths) as a selection. If you
want to load only one of the sub-paths as a selection, first select it, then click on the
Load path as a selection button at the
bottom of the Paths palette.