User Manual

Blend
The Blend slider determines the percentage of the affected image that is mixed with original
image. It blends in more of the original image as the value gets closer to 0.
This control is a cloned instance of the Blend slider in the Common Controls tab. Changes
made to this control are simultaneously made to the one in the common controls.
Color Scale (RGBA)
These Scale sliders are used to adjust the amount of glow applied to each color channel
individually, by tinting the glow.
Common Controls
Settings Tab
The Settings tab in the Inspector is also duplicated in other Blur nodes. These common controls
are described in detail at the end of this chapter in “The Common Controls” section.
Unsharp Mask [USM]
The UnsharpMask node
Unsharp Mask Introduction
Unsharp masking is a technique used to sharpen only the edges within an image. This node is
most often used to correct for blurring and loss of detail in low-contrast images; for example, to
extract useful detail from long exposure shots of faraway galaxies.
This filter extracts a range of frequencies from the image and blurs them to reduce detail. The
blurred result is then compared to the original images. Pixels with a significant difference
between the original and the blurred image are likely to be an edge detail. The pixel is then
brightened to enhance it.
Inputs
The two inputs on the Unsharp Mask node are used to connect a 2D image and an effect mask
for limiting the effect.
–
Input: The orange input is used for the primary 2D image for the Unsharp Mask.
–
Effect Mask: The blue input is for a mask shape created by polylines, basic primitive
shapes, paint strokes, or bitmaps from other tools. Connecting a mask to this input
limits the Unsharp Mask to only those pixels within the mask. An effect mask is
applied to the tool after it is processed.
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