How to Increase Contrast in Illustrator
By Elizabeth Mott
Unlike Adobe Photoshop, which offers contrast adjustments and adjustment layers, Adobe Illustrator doesn't include a command or tool that explicitly addresses the need to increase color contrast. Despite Illustrator's lack of processes designed for this specific purpose, you can use it to achieve the same effects by altering object colors using the Hue, Saturation and Brightness color model. HSB separates hue, which defines shade or tone, from saturation's vividness and brightness's gradation from light to dark. You can combine two of these parameters to achieve the contrast adjustments you use in other graphics applications.
Press "V" to activate the Selection tool in Adobe Illustrator. Use the Direct Selection tool or its keyboard shortcut -- "C" -- to access objects that form part of a group.
Click on an object that you created with Illustrator's text or drawing tools to select it for editing. In the Illustrator toolbox, double-click on the Fill color swatch to bring up the Color Picker.
Set the B -- for brightness -- value to a higher number to make your object's fill become lighter. Raise the S -- for saturation -- value to increase the intensity of the color. In combination, raising these two attributes increases contrast by broadening tonal range.
Click on the "OK" button to apply your color alteration to the object or objects you selected. To add the color you just created to the Swatches panel so you can apply it to other objects, drag the Fill color swatch to the Swatches panel.
- Once you reach 100 percent saturation and 100 percent brightness, you can't increase contrast further.
- HSB describes color differently from CMYK or RGB, which rely on additive or subtractive primary color elements. Nonetheless, HSB creates colors that can fit within the color definitions used by the other systems.
- Change the CMYK or RGB channel values in the Color Picker to view the impact of adjusting these aspects of color on HSB values.
- Highly bright, saturated colors may not reproduce properly in the CMYK color gamut. They can exceed the range of colors that CMYK output devices can print.
- Information in this article applies to Adobe Illustrator CS6 and Adobe Illustrator CC. It may differ slightly or significantly with other versions or products.
Elizabeth Mott has been a writer since 1983. Mott has extensive experience writing advertising copy for everything from kitchen appliances and financial services to education and tourism. She holds a Bachelor of Arts and Master of Arts in English from Indiana State University.