Adobe photoshop cs2 Manuel D’Utilisation
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ADOBE PHOTOSHOP CS2
User Guide
To adjust RGB color display for cross-platform variations (ImageReady)
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Choose View > Preview and choose an option for adjusting the color display:
Uncompensated Color
Displays the image with the monitor gamma uncorrected.
Standard Macintosh Color
Displays the image with a gamma value of 1.8.
Standard Windows Color
Displays the image with a gamma value of 2.2.
Use Embedded Color Profile
Uses the embedded profile to display the image.
These options adjust color display only. No changes are made to pixels in the image.
You can edit your image in one window and view the same image with a different gamma value in a second window.
Choose Window > Arrange > New Window For [File Name]. With the new window active, choose View > Preview
Choose Window > Arrange > New Window For [File Name]. With the new window active, choose View > Preview
and then choose a different gamma than the one used in the first window.
To adjust RGB color display to match Photoshop color display (ImageReady)
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Choose View > Preview > Use Embedded Color Profile.
Note: To use the Use Embedded Color Profile command in ImageReady, you must first save the original image, with the
color profile embedded, in Photoshop. Keep in mind that ImageReady does not use profiles in PNG or TIFF files.
color profile embedded, in Photoshop. Keep in mind that ImageReady does not use profiles in PNG or TIFF files.
Channels and bit depth
About color channels
A working knowledge of color channels and bit depth is key to understanding how Photoshop stores and displays
color information in images. Every Photoshop image has one or more channels, each storing information about color
elements in the image. The number of default color channels in an image depends on its color mode. For example, a
CMYK image has at least four channels, one each for cyan, magenta, yellow, and black information. Think of a
channel as analogous to a plate in the printing process, with a separate plate applying each layer of color.
color information in images. Every Photoshop image has one or more channels, each storing information about color
elements in the image. The number of default color channels in an image depends on its color mode. For example, a
CMYK image has at least four channels, one each for cyan, magenta, yellow, and black information. Think of a
channel as analogous to a plate in the printing process, with a separate plate applying each layer of color.
In addition to these default color channels, extra channels, called alpha channels, can be added to an image for storing
and editing selections as masks, and spot color channels can be added to add spot color plates for printing.
and editing selections as masks, and spot color channels can be added to add spot color plates for printing.
An image can have up to 56 channels. By default, bitmap, grayscale, duotone, and indexed-color images have one
channel; RGB and Lab images have three; and CMYK images have four. You can add channels to all image types
except Bitmap mode images.
channel; RGB and Lab images have three; and CMYK images have four. You can add channels to all image types
except Bitmap mode images.
See also
About bit depth
Bit depth—also called pixel depth or color depth—measures how much color information is available for displaying
or printing each pixel in an image.
or printing each pixel in an image.