Apple Shake 4 - Manual (Page 878)

878 Chapter 28 Filters
The next image is the result of increasing the lGain (or rGain, gGain, and bGain on a
per-channel basis), and increasing the range of the grain. This results in making the
diagonal line both lighter and darker simultaneously.
The following two images show the result of modifying the Bias and Gain. In the first
image, the rBias is lowered (looking only at the red channel) to -.5. The grain shifts
downward from the diagonal line, making it darker. This affects both the lighter grain
(the dots above the original diagonal line) and the darker grain (the dots below the
original diagonal line). To adjust only the lighter or darker grains, use the offset sliders.
The second image shows a rLowOffset of .5, squeezing only the darker grains, leaving
only lighter grains.
In the following images, the left image shows the standard softness. The middle image
has a softness of 10, and the right image has a softness of -10.