User Manual

Table Of Contents
Red Level, Green Level, Blue Level
These color sliders tune the level of the difference channels to help separate the color. When
the background color is green, Red and Blue level options are provided. When the background
color is blue, Red and Green level options are provided.
Background Correction
Depending on the background color selected above, the keyer iteratively merges the pre-
keyed image over either a blue or green background before processing it further.
In some instances, this leads to better, more subtle edges.
Matte Separation
Matte Separation performs a pre-process on the image to help separate the foreground from
the background before color selection. Generally, increase this control while viewing the Alpha
to eliminate the bulk of the background, but stop just before it starts cutting holes in the subject
or eroding fine detail on the edges of the matte.
Pre Matte Range
These R,G,B, and Luminance range controls update automatically to represent the current color
selection. Colors are selected by selecting the Ultra Keyer node’s tile in the node tree and
dragging the Eyedropper into the viewer to select the colors to be used to create the matte.
These range controls can be used to tweak the selection slightly, although selecting colors in
the viewer is all that is required.
Lock Color Picking
This checkbox prevents accidentally selecting more colors from the view. It is a good idea to
activate this checkbox once the color selection is made for the matte. All other controls in the
node remain editable.
Pre Matte Size
The Pre Matte Size control can be used to soften the general area around the keyed image.
This is used to close holes in the matte often caused by spill in semitransparent areas of the
subject. This can cause a small halo around the subject, which can be removed using the Matte
Contract tools found later in the tool.
Reset Pre Matte Ranges
This discards all color selection by resetting the ranges but maintains all other slider and
control values.
Chapter – 98 Matte Nodes 2187