Appropriate Formats - Adobe 65023809 - Creative Suite 4 Master Collection Printing Manual

If such an image is not converted to grayscale, even very slight color shifts on press could pro-
duce a color cast in the printed image. An image that's color—but appears grayscale—still dis-
plays its color mode in the document's title bar. Look for the CMYK or RGB identifier after the
image name in the title bar. Just finish the conversion by choosing Image > Mode > Grayscale,
and update the image links if the image is used in an InDesign layout or Illustrator file.
Multitone images (duotone, tritone)
Multitone images such as duotones, tritones, and quadtones are actually grayscale images con-
taining embedded transfer curves. The transfer curves contain information about what colors are
generated during output, as well as the relative values of those colors. Most commonly, process
black is one component of a duotone or tritone, which can cause a common problem you may
encounter with multitone images supplied by customers.
The initial dialog box for duotone options (Image > Mode > Duotone) automatically populates
the black ink name for you. Unless the image is intended to print with a spot black ink rather
than process black, this default black ink should not be changed. Some users think that they
should manually pick a black ink. This results in an additional, unintended plate being generated
during output.
Duotone Settings
The default settings for a duotone image use process black for the black plate . Choosing Pantone Black instead,
generates an extra, unwanted black plate .
To fix this problem, open the image in Photoshop, and choose Image > Mode > Duotone to open
the Duotone Options dialog box. Highlight the incorrect black ink name, and change it to Black,
with a capital "B," to indicate standard process black. Update the image link in InDesign or
Illustrator as necessary, and delete the extraneous ink from the Swatches palette of the target
document.
On Windows, the duotone presets are found in: C:\Program Files\Adobe\Adobe Photoshop CS4\
Presets\Duotones. In Mac OS, the Macintosh, the presets are found in: Applications/Adobe
Photoshop CS4/Presets: Duotones. To save a custom preset for multitone images, click Save in
the Duotone Options dialog box. Save to the default location, or choose an alternative location.
Photoshop creates a file with the .ado extension. To load a duotone preset, click Load in the
Duotone Options dialog box and navigate to the desired preset.
Bitmap images
Bitmap images (also called bilevel or line art scans) consist of only black and white (or black and
transparent) pixels, with no intermediate shades of gray. Such images can be colorized when
placed into Illustrator or InDesign, taking on whatever color is applied. The black areas of the
bitmap image become the color of the applied swatch, while the white areas remain unaffected.

Appropriate Formats

Some of the old restrictions on image formats no longer apply in Creative Suite. In modern
workflows, you are not limited to using TIFF and EPS files; more modern formats such as native
Photoshop and Acrobat PDF provide more flexibility and function. While you may feel more
comfortable with the time-tested formats, the newer formats offer significant benefits. In other
words, do not fear the new approaches, and do not assume that you have to convert Photoshop
files to something more familiar in order to image a job successfully. In a full Adobe Creative
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