Game Development Reference
the fact that I've only applied this effect once, and I'm not using a
Spill Suppressor or any other effect here. Remember that for the
best results, it's best to constantly change the view to the gray-
scale matte so that you know exactly how transparent your pixels
are (Fig. 10.23).
Figure 10.23 The quite
impressive (and quick) results
with the Linear Color Key effect.
The Luma Key Effect
The Luma Key effect is similar to the Extract effect in that it
attempts to pull a key by looking at a layer's brightness, and key-
ing out either light or dark values. The Luma Key effect doesn't
give you as much control (as the Extract effect also allows you to
adjust individual color channels), but it is easier to use, and the
results are comparable.
For this look at the Luma Key effect, we'll be using the Luma
Key.aep project from the Chapter 10 folder, which is identical to
the project we looked at with the Extract effect. That way, you can
compare and contrast the results with what we saw of the Extract
effect a little earlier.
Apply the Luma Key effect to the fi reworks layer. The default
Key Type is Key Out Darker, which removes dark pixels. You can
change this value to Key Out Brighter to eliminate bright areas.
To remove any pixels, you need to increase the Threshold value.
The Tolerance parameter functions similarly to Threshold, but
only works when Key Out Similar or Key Out Dissimilar is chosen
as the Key Type. When Key Out Similar or Key Out Dissimilar is
chosen as the Key Type, you can use both the Tolerance and the
Threshold properties simultaneously to key out a wider range of
tonal values. Key Out Similar is very much like Key Out Darker,