Keying - Nuke 101: Professional Compositing and Visual Effects - page 313

• Blue/Green Weight: This property changes the density of the generated
matte by adding or subtracting the blue or green areas of the image. If
you're keying out blue, then it's the green channel that is being used. If
you're keying out green, then it's the blue channel.
• Luminance Match: This property first needs to be turned on with the
check box. Once it is on, the Screen Range slider will affect light areas
and firm up the matte there.
• Luminance Level: This property has no effect anymore and will be re-
moved in the next version of the software.
Figure 7.19. The IBKGizmo's properties.
To properly see the adjustments as you change property values, you should ac-
tually be looking at a composite. This means you need to place the keyed fore-
ground on top of your background image.
16. Select IBKGizmoV3_1 and insert a Merge node after it by pressing the M key.
17. Connect Merge1's B input to Read1's output ( FIGURE 7.20 ) .
Figure 7.20. Your tree should look like this after adding the Merge node.