User Guide

Canvas 12 User Guide
CMYK Color image mode
CMYK color mode is based on the four color inks used in commercial printing (and by some desktop
printers): cyan, magenta, yellow, and black. Some color scanners can produce CMYK images.
In a CMYK color image, each pixel has a cyan, magenta, yellow, and black component. Each of these
color channels has 256 intensity levels. The combination of the intensity value in each channel
creates each pixel’s color. Because monitors are RGB devices, they can’t display CMYK colors directly.
However, Canvas attempts to display CMYK images as they will appear when printed.
LAB color image mode
The Commission Internationale d’Eclairage (CIE) developed the LAB color mode as an international
color standard to overcome the device dependency of the RGB and CMYK modes. In a LAB color mode
image in Canvas, each pixel has one lightness and two color components. The Lightness (L) channel
has 256 levels of intensity. The two color channels, labeled A and B, provide a color range from red to
green and yellow to blue, respectively.
Some companies sell collections of images in LAB color mode. Editing LAB color mode images with
some filters or painting tools can have interesting and unpredictable effects.
Duotone image mode
In traditional graphics arts reproduction, a “duotone” is a grayscale image printed with black and an
additional color. Canvas lets you create duotone images, as well as “monotone,” “tritone,” and
“quadtone” images (printed with one, three, or four colors, respectively).
The term “Duotone” refers to the Duotone image mode, not just to images printed with two
inks. In Duotone mode, an image can be printed as a monotone, duotone, tritone, or
quadtone.
Printing images as duotones can add interest and increase the tonal range reproduced from
grayscale photographs, without the additional expense of printing full-color images. The duotone
effect can be subtle or striking, depending on the color used and the amount added to the image. In
any case, the additional colors are used to reproduce the gray values in the image, rather than to
reproduce specific colors.
To create a monotone, duotone, tritone, or quadtone in Canvas, you must convert a Grayscale image
to Duotone mode. Unlike other image modes, once an image is converted to Duotone mode, you
cannot work with individual image channels. Instead, you can adjust curves for each color “channel”
in the Duotone Options dialog box.
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