There are many tweaks that can be made to PhotoShop's preferences, depending on RAM, video card, and number of processors and hard drives. The screenshots that follow are from the Mac version of Adobe PhotoShop CS5.
First: one of the most annoying aspects of the Adobe Suite for OS X is that it alters the established keyboard shortcut for preferences in every program (CMD-,) to its own (CMD-K). Press that combination to start up the Preferences panel for PhotoShop.
In the General tab that appears, change the Image Interpolation setting at the top to Bicubic Sharper: in web development, you are more likely reducing original images to sizes that can best fit on web pages. Also, turn off "Use Shift key for tool switch". This is the second most annoying feature, which you have just nullified: you can now switch tools on the tool bar, such as variations on the marquee tool (the M key), with repeated presses to a single key on the keyboard.
Under Units and Rulers, change the units for both Rulers and Type to pixels.
Optional: if you have a second hard drive with a high-speed interconnect, choose that second drive as the scratch disk under the Performance tab.
To speed up PhotoShop, you may wish to turn Image Previews in the File Handling pane to Never Save.
Finally, we need to recognize that PhotoShop's suggestions for "Web" canvas sizes when creating a new document are incorrect, with the exception of the lowest four, which are standard advertising banner sizes. PhotoShop suggests full screen resolution as the size for web pages, and ignores the fact that the browser window will have a tab bar, scrollbars, and operating system UI components present, reducing the "screen real estate" significantly. The browser window may not even be maximised, especially at higher screen resolutions, reducing the available size even further. In addition, PhotoShop's suggestions imply that you will be creating a fixed width design mockup; generally speaking, you should be creating a fluid design instead.
However, if you are creating a fixed-width design, or wish to use some figures as a rough guide for a mockup, the following are more accurate dimensions to use:
|Targeted Screen Resolution||Actual Browser Window Size (Maximized) =|
PhotoShop Canvas Size
|1024 × 768||955 × 600|
|1200 × 1024||1180 × 850|
|1600 × 1200||1580 × 1030|
Enter these dimensions as Custom sizes when creating a new PhotoShop document for mocking up a web page, but be aware of the increasing need for responsive designs.
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