User Manual

Inspector
Controls Tab
The Controls tab in the Difference Keyer contains all the parameters for adjusting the quality of
the matte.
Threshold
This range slider sets the lower threshold using the handle on the left and sets the upper
threshold using the handle on the right. Adjusting them defines a range of difference values
between the images to create a matte.
A difference below the lower threshold setting becomes black or transparent in the matte.
Any difference above the upper threshold setting becomes white or opaque in the matte.
The difference values in the range in between create a grayscale matte.
Filter
This control selects the filtering algorithm used when applying a blur to the matte.
 Box: This is the fastest method but at reduced quality. Box is best suited for minimal
amounts of blur.
 Bartlett: Otherwise known as a Pyramid filter, Bartlett makes a good compromise
between speed and quality.
 Multi-box: When selecting this filter, the Num Passes slider appears and lets you
control the quality. At 1 and 2 passes, results are identical to Box and Bartlett,
respectively. At 4 passes and above, results are usually as good as Gaussian, in less
time and with no edge “ringing.”
 Gaussian: The Gaussian filter uses a true Gaussian approximation and gives excellent
results, but it is a little slower than the other filters. In some cases, it can produce an
extremely slight edge “ringing” on floating-point pixels.
Blur
This blurs the edge of the matte using the method selected in the Filter menu. A value of zero
results in a sharp, cutout-like hard edge. The higher the value, the more blur.
Chapter – 98 Matte Nodes 2160