User Guide

Using Image Effects296
The Glass Distortion effect.
There are five sources of displacement
information:
• Paper uses the information in a
paper texture to displace pixels.
More displacement is applied to
light areas of the texture and less to
dark areas. Paper texture is good
for creating the pebbled glass
effect. Unless you want frosted
glass, you’ll probably want to
increase the scale of the paper.
• 3D Brush Strokes uses the
difference in luminance between
the clone source and the current
document.
• Image Luminance uses the light
and dark areas in the current
document to determine the
intensity of distortions.
• Original Luminance uses the
clone source’s luminance. Use a
tessellation as the clone source to
produce a bumpy glass effect.
• [Alpha channel] or [Layer mask]
uses the luminance of a channel or
layer mask. More distortion
appears in the light areas of the
channel. You must have a saved
alpha channel or layer mask to use
this source.
This is a good choice for a
controlled distortion map. For
example, gradations in the channel
lead to a progressive distortion
effect. Shapes in the channel
produce distortions with distinct
outlines.
There are three types of maps:
• Refraction displaces pixels in the
same way that an optical lens
bends light. This is the best map
type for distortions you’d expect
from looking through glass.
• Vector Displacement moves pixels
in a specific direction.
• Angle Displacement moves pixels
in different directions.
To apply a glass distortion effect:
1 Select a layer or area of the canvas.
If you want to apply the effect to
the entire image, make sure there
are no selections.
2 Choose Effects menu > Focus >
Glass Distortion.
3 In the Glass Distortion dialog box,
choose a source from the Using
pop-up menu.
The amount of displacement
depends on the value assigned to
the image pixels from the Using
source.
If you want to work with an
inversion of the selected source,
enable the Inverted check box.
4 Adjust the Softness slider to
control the transitions between
displaced colors.
Increasing Softness creates more
intermediate steps, which
produces a smoother distortion. If