• F (Cycle Screen Modes) — Switch between normal screen, full screen with task bar without title bar, and full screen with black background. Works great when used in conjunction with Tab to hide toolbars — maximum working space, no distractions.
• X (Switch Colors) — Swap your foreground and background colors. Very handy when working with masks.
• D (Default Colors) — Reset your foreground and background colors to black and white, respectively.
• Ctrl + ‘+’/'-’ (Zoom In/Out) — Quickly zoom in or out without changing your current tool.
• Alt + Mouse Scroll (Zoom In/Out) — Fastest way to zoom — scroll up to zoom in, and scroll down to zoom out.
• Ctrl + Alt + Z (Step Back) — Ctrl + Z is OK if you catch a mistake immediately after it happens, but this command will continue to march its way up the history tree.
• Ctrl + S (Save) — You should get in the habit of just hitting this combo on impulse about every 5 to 10 minutes. Also use Ctrl + Alt + Shift + S to bring up the save for web dialog.
• Ctrl + Alt + Shift + N (New Layer No Dialog) — Quickly insert a new empty layer on top of the active layer. Get rid of the Alt key to bring up the new layer dialog for more options.
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Subject: photo shop short cuts 