Operation Manual

Working with bitmap color modes | 539
The Intensity slider is not available for the Halftone conversion option.
Changing bitmaps to duotones
To convert an image to a duotone, you change a bitmap to the grayscale color mode and enhance it using one to four additional colors,
giving the image greater tonal depth.
The following four variations of the color mode correspond to the number of additional inks:
• Monotone — a grayscale image colored with a single tone
• Duotone— a grayscale image colored with two tones. In most cases, one is black and the other is colored.
• Tritone — a grayscale image colored with three tones. In most cases, one is black and the other two are colored.
• Quadtone — a grayscale image colored with four tones. In most cases, one is black and the other three are colored.
Adjusting tone curves
When you change an image to a duotone, a tone curve grid that represents the dynamic tone curves that are used throughout the
conversion is displayed. The horizontal plane (x-axis) displays the 256 possible shades of gray in a grayscale image (0 is black; 255 is white).
The vertical plane (y-axis) indicates the intensity of a color (from 0 to 100 percent) that is applied to the corresponding grayscale values. For
example, a grayscale pixel with a color value of 25 is printed with a 25-percent tint of the color. By adjusting the tone curves, you can control
the color and intensity of the tone that is added to an image.
Saving and loading inks
You can save an adjusted duotone tone curve and ink settings and then load them for use with other bitmaps.
Specifying how overprint colors display
When you change an image to a duotone, you can specify the colors to overprint when you print an image. Overprint colors are used to
preserve color integrity when inks overlap. When you display the image, each color is applied on the screen in sequence, creating a layered
effect.
You can view all instances in which the colors you choose for the duotone conversion overlap. Associated with each instance is the color that
is produced by the overlap. You can also choose new overprint colors to see how they overlap.
Duotones hold their color ink information when you save to EPS, PDF, Corel DESIGNER (DES), and Corel PHOTO-PAINT (CPT) file formats.
Other file formats don’t support duotone images.
To change an image to a duotone
1 Click a bitmap.
2
Click Bitmaps Mode Duotone (8-bit).
3 Click the Curves tab.
4 Choose a duotone type from the Type list box.
5 Double-click an ink color in the Type window.
6 In the Select color dialog box, choose a color, and click OK.
If you want to adjust the color’s tone curve, click the ink tone curve on the grid to add a node, and drag the node to adjust the
percentage of color at that point on the curve.
7 Repeat steps 5 and 6 for each ink color you want to use.
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You can also 
Display all the ink tone curves on the grid. Enable the Show all check box.