User Manual

If the foreground image has a shadow in it that you want to keep in the composite, do
not select any of the dark screen pixels in the shadow. This keeps the shadow with the
rest of the foreground image.
Clean Background Noise
If there are any white or light gray regions in the dark screen area, this is referred to as “noise.”
Technically, it is varying shades of the screen color that did not get picked up on the first
sample and should be removed. You remove background noise using the Clean Background
Noise button.
1 From the View Mode menu in the Inspector, select Black.
2 Above the viewer, click the Alpha Channel/RGB button.
The image displayed changes to a black and white “matte” view of the image.
3 Click the Clean Background Noise button.
4 Drag the mouse pointer through these white or light gray regions that should be
pure black.
Primatte processes the selection and eliminates the noise.
5 Repeat this procedure as often as necessary to clear the noise from the
background areas.
Selecting Gain/Gamma from the viewer’s Options menu to increase the brightness or
gamma allows you to see noise that would otherwise be invisible.
Primatte viewer Options menu
You do not need to remove every single white pixel to get good results. Most pixels
displayed as a dark color close to black in a key image are considered transparent and
virtually allow the background to be the final output in that area. Consequently, there is
no need to eliminate all noise in the screen portions of the image. In particular, if an
attempt is made to remove noise around the foreground subject meticulously, a smooth
composite image is often difficult to generate.
TIP: When clearing noise from around loose, flying hair or any background/
foreground transitional area, be careful not to select any of the areas near the
edge of the hair. Leave a little noise around the hair as this can be cleaned up
later using the Fine Tuning tools.
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