Quick links to procedures on this page:
You can use the Sketch effect to generate a black and white pencil outline of a photograph. You can then use the outline as a guide for applying color, which is a useful technique for starting a painting. For more information, see Choosing a painting workflow.
To store the settings for the effect, you can create a preset. This allows you to quickly apply the settings to another image.
Before (left) and after (right) applying the Sketch effect.
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Choose Effects  Surface Control Sketch. |
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In the Sketch dialog box, adjust any of the following sliders: |
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Sensitivity — determines sensitivity to detail. Low values detect only the main edges. High values detect the main edges as well as thin lines, such as the lines around a person’s eyes. |
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Smoothing — determines how much noise is filtered out. Higher values result in wider, lighter, and blurrier lines. |
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Grain — determines how much of the paper grain is revealed in the sketch marks. Move this slider to the right to show more of the paper grain. |
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Threshold High and Threshold Low — removes noise after edge detection. Threshold High is used to flag light pixels which may be just noise in the image. Threshold Low is used to test surrounding pixels. |
You can also apply a preset sketch effect by choosing a preset from the Preset list box.
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Choose Effects Surface Control Sketch. |
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In the Sketch dialog box, modify any of the settings. |
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In the Add Preset dialog box, type a name in the Preset Name box. |
You can delete a preset sketch effect by choosing it from the Preset list box and clicking the Delete button.
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