Keying - Nuke 101: Professional Compositing and Visual Effects - page 303

HueKeyer
The HueKeyer is a straightforward chroma keyer. It has one input for the image you want
to key. HueKeyer produces an alpha channel by default, and does not premultiply the im-
age.
Let's connect one HueKeyer node.
1. SelectRead2andinsertaHueKeyernodefromtheKeyertoolboxafterit( FIGURE
7.5 ) .
Figure 7.5. Again, for reference, here is the HueKeyer's Properties panel.
HueKeyer's interface consists of a graph editor where the X axis represents hue,
and the Y axis represents amount to be keyed. By creating a point on the graph at
a certain hue and pulling the graph up to a value of 1, you tell HueKeyer that this
hue should be 100% gone.