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Channels panel overview



The Channels panel lists all channels in the image—composite channel first (for RGB, CMYK, and Lab images). A thumbnail of the channel’s contents appears to the left of the channel name; the thumbnail is automatically updated as you edit the channel.

Channel types

A.
Color channels

B.
Spot channels

C.
Alpha channels

Display the Channels panel

 Choose Windows > Channels.

Resize or hide channel thumbnails

 Choose Panel Options from the Channels panel menu. Click a thumbnail size or click None to turn off the display of thumbnails.

Viewing thumbnails is a convenient way of tracking channel contents; however, turning off the display of thumbnails can improve performance.