Adobe Photoshop CS3 - Manual (Page 507)

PHOTOSHOP CS3
User Guide
500
You can use the Info palette to display ink percentages when you’re working with duotone images. Set the readout
mode to Actual Color to determine what ink percentages will be applied when the image is printed. These values
reflect any changes you’ve entered in the Duotone Curve dialog box.
See also
“Curves overview” on page 163
Specifying overprint colors
Overprint colors are two unscreened inks printed on top of each other. For example, when you print a cyan ink over
a yellow ink, the resulting overprint color is green. The order in which inks are printed, as well as variations in the
inks and paper, can significantly affect the final results.
To predict how colors will look when printed, use a printed sample of the overprinted inks and adjust your screen
display accordingly. Keep in mind that this adjustment affects only how the overprint colors appear on-screen, not
when printed. Before adjusting these colors, make sure to calibrate your monitor.
Adjust the display of overprint colors
1 Choose Image > Mode > Duotone.
2 Click Overprint Colors. The Overprint Colors dialog box shows how the combined inks will look when printed.
3 Click the color swatch of the ink combination that you want to adjust.
4 Select the desired color in the color picker, and click OK.
5 Repeat steps 3 and 4 until you are satisfied with the ink combination. Then click OK.
Saving and loading duotone settings
Use the Save button in the Duotone Options dialog box to save a set of duotone curves, ink settings, and overprint
colors. Use the Load button to load a set of duotone curves, ink settings, and overprint colors. You can then apply
these settings to other grayscale images.
Photoshop includes several sample sets of duotone, tritone, and quadtone curves. These sets include some
commonly used curves and colors. Use these sets as starting points when you create your own combinations.
View the individual colors of a duotone image
Because duotones are single-channel images, your adjustments to individual printing inks are displayed as part of
the final composite image. In some cases, you may want to view the individual “printing plates” to see how the
individual colors will separate when printed (as you can with CMYK images).
1 After specifying your ink colors, choose Image > Mode > Multichannel.
The image is converted to Multichannel mode, with each channel represented as a spot color channel. The contents
of each spot channel accurately reflect the duotone settings, but the on-screen composite preview may not be as
accurate as the preview in Duotone mode.
Note: If you make any changes to the image in Multichannel mode, you can’t revert to the original duotone state (unless
you can access the duotone state in the History palette). To adjust the distribution of ink and view its effect on the
individual printing plates, make the adjustments in the Duotone Curves dialog box before converting to Multichannel
mode.