FIND THE CENTER OF ANY DOCUMENT

Need to find the exact center of your image? All you need is a layer filled with your Foreground color, and Photoshop will do the rest (okay, you have to do a little, but Photoshop will certainly help). First, click on the Create a New Layer icon in the Layers palette and press Option-Delete (PC: Alt-Backspace) to fill it with your Foreground color. Make your rulers visible (press Command-R [PC: Control-R]) and drag a guide down from the top ruler. When you get close to the center of the image, the guide will automatically snap to the exact horizontal center. Do the same with the side ruler, and it automatically snaps to the vertical center of your image. (Note: If there's not any snapping going on, be sure Snap is turned on under the View menu.)