Operation Manual

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Preferences— Advanced Color

Advanced Color

White Point, Gray Point, Black Point, and Auto Contrast

The “Advanced Color” category is used to specify output

col ors for the black, white, and gray points and to change

the size of the area sampled when the eyedropper tools in

the “Curves” palette are used. It is also controls the portion

of the tone range excluded in auto contrast operations.

White-, Gray-, and Black-Point Targets

The targets in the “RGB” and “Grayscale” tabs specify de-

fault out put values for the white, gray, and black points in

each color model. The fac to ry default set ting for white point

is 255 for each channel, which displays as white on most

com put er mon i tors. The factory default for the gray point

is 128, which displays as a neutral gray. The de fault for the

black point is zero, which dis plays as black. To restore fac-

tory de faults for the color mod el in the selected sheet, click

Reset.

The Master Channel

To set the white and black points for the master channel in the RGB

color model, select RGB in the “Curves” palette channel menu, click the

white- or black-point eyedropper tool while pressing Ctrl (Windows) or

option (Macintosh), and sample the image.

Output Values

Although output values in the “Advanced Color” palette range from

zero to 255, cal cu la tions are per formed at a pre ci sion of six teen bits.