User Guide

Canvas 12 User Guide
You can apply filters to one or more selected paint objects. If a single paint object is in edit
mode, a filter applies to the entire image or an active selection.
Image Measurement command can be applied to paint objects that are selected or in edit
mode.
Many commands in the Adjust menu can be used to uniformly adjust one or more selected
paint objects, or a paint object in edit mode.
Working with image-adjustment dialog boxes
Some dialog boxes for image-editing commands include histograms and preview options to help you
achieve the effect you want.
Using the Preview option
Most dialog boxes for image-adjustment commands include a Preview check box. Select the Preview
option to see how settings affect the image. Preview is available only when a single paint object is in
edit mode.
Understanding histograms
A histogram plots the relative number of pixels in each brightness level in an image.
In the above, shorter bars on the left indicate that the image doesn’t contain large areas of very dark
pixels. Higher bars toward the right of the graph show that the image contains large areas of medium
and very bright pixels.
To view an image’s histogram at any time:
With an image selected or in edit mode, choose Image | Histogram.
Consolidating colors
The Threshold and Posterize commands let you consolidate color values in an image or selection.
Besides producing interesting effects with these commands, you can use them in alpha channels to
help isolate areas within an image.
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