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A popular high-end image editor for the Macintosh and Windows from Adobe. The original Mac versions were the first to bring affordable image editing down to the personal computer level in the late 1980s. Since then, Photoshop has become the de facto standard in image editing. Although it contains a large variety of image editing features, one of Photoshop's most powerful capabilities is layers, which allows images to be rearranged under and over each other for placement. Photoshop is designed to read from and convert to a raft of graphics formats, but uses its own native format for layers (.PSD extension). See Photoshop plug-in, Photoshop actions and Photoshopped.

Layers Are Often Essential
It would be extremely difficult to develop the CD-ROM jewel case cover below without layers. If only one layer were available, each and every image element would have to be aligned perfectly on top of the existing image. There would be no way to change the placement because each piece becomes merged into a single bitmapped image, replacing what was previously there. Without having all elements in view and being able to move them around in different ways, it would be virtually impossible to derive the most pleasing effect. See image editor.

Photoshop Layers
The image above is built in 23 layers plus a background layer, enabling the individual elements to be moved independently of the others. The layer window (below) shows the layers. The arrow is pointing to the view option (the "eye") in the chip shadow layer. Clicking the eye toggles between making the layer invisible and bringing it back into view.

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Before/After Your Search Term
photonicsPhotoshop actions
photooptic memoryPhotoshop Elements
photorealisticPhotoshop filter
photorealistic image synthesisPhotoshop plug-in
Photos for the Macphototransistor

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