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482
Adobe Photoshop Help
Printing (Photoshop)
Using Help
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Contents
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482
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.
The Adobe Photoshop application includes several sample sets of duotone, tritone, and
quadtone curves. These sets include some of the more commonly used curves and colors
and are useful as starting points for creating your own combinations.
Viewing individual printing plates
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).
To view the individual colors of a duotone image:
1
After specifying your ink colors, choose Image > Mode > Multichannel.
The image is converted to a multichannel image, 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.
Important:
If you make any changes to the image in Multichannel mode, you will be
unable to 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.
2
Select the channel you want to examine in the Channels palette.
3
Choose Edit > Undo Multichannel to revert to Duotone mode.
Printing duotones
When creating duotones, keep in mind that both the order in which the inks are printed
and the screen angles you use dramatically affect the final output.
Click the Auto button in the Halftone Screens dialog box to set the optimal screen angles
and frequencies. (See
“Selecting halftone screen attributes” on page 475
.) Make sure that
you select Use Accurate Screens in the Auto Screens dialog box if you’re printing to a
PostScript Level 2 (or higher) printer or an imagesetter equipped with an Emerald
controller.
Note:
The recommended screen angles and frequencies for quadtones are based on the
assumption that channel 1 is the darkest ink and channel 4 is the lightest ink.
You do not have to convert duotone images to CMYK to print separations—simply choose
Separations from the Profile pop-up menu in the Color Management section of the Print
dialog box. (See
“Printing color separations” on page 483
.) Converting to CMYK mode
converts any custom colors to their CMYK equivalents.