Ultimatte-9 Operations Manual
March 1, 2000
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The Shadow Removal SCREEN control is adjusted while viewing the composited image. Usually
it is best to adjust The Shadow Removal THRESHOLD control first, followed by the Shadow
Removal SCREEN control.
3. Shadow Removal Threshold
The Shadow Removal THRESHOLD control allows the user to separate shadow areas from non-
shadow screen areas. Evenly lit screens allow best separation of shadows. As lighting
unevenness increases, only shadows that are darker than the darkest area of the screen can be
separated.
The Shadow Removal THRESHOLD control is best adjusted while viewing the matte. At its
default setting, the Shadow Removal THRESHOLD control considers the entire matte signal
range to be shadow. As the control is turned higher, only matte values below the threshold are
considered shadows.
4. Clean Up Level
The Clean Up Level can be used to remove evidence of imperfections in the backing such as
scuffmarks, seams, or unwanted shadows. The Clean Up Level solves these problems at the
expense of fine detail on the edges of the FG subject. Use Clean Up Level sparingly as it can
produce a hard-edged, cutout look to the composite image. Clean Up Level can also be used to
reduce noise in the BG area of the matte signal, in addition to the residue noise left in the backing
area of the processed FG image. Clean Up Level could be, in some cases, an alternative to
increasing the BG Level Balance control setting. Either adjustment involves a compromise in the
overall look of the image.
The problem with Clean Up Level is that there is no way to distinguish between imperfections in
the backing and subtle detail on FG edges or transparent areas, including shadows.
The final adjustments of this control should be made while viewing the composited image. The
detrimental effect that the Clean Up Level has on the edges of FG subjects cannot be properly
evaluated except by viewing the composite.
5. Clean Up Threshold
The Clean Up Threshold control
is used in conjunction with the Clean Up Level control. It sets a
reference level in the matte signal, above which the Clean Up Level control will be effective, but
below this threshold the matte signal will not be affected. In certain cases it can eliminate small
screen imperfections e.g. scuff marks and noise from the composite image, with no effect on
shadows and edge detail that exists below this threshold level.
When the Clean Up Threshold control
is set to 0%, Clean Up Level is applied to the entire matte
signal.
6. Clean Up Balance
This control shoud be used only when the Clean Up control has been adjusted. It determines how
much influence the Clean Up control will have on the foreground and background images. View
both the matte and the composite when adjusting this control. If, using the Clean Up control
caused glowing on dark edges,
Clean Up Balance
control can be used to reduce the problem.
The Clean Up Balance
control is a fine-tuning adjustment of the Clean Up Level control. It
normally does not need to be used, but it might help optimize the look of the edges of the FG
subject after Clean Up Level has been advanced. It has no effect when Clean Up Level control is
off (at minimum setting). The Clean Up Balance
control
applies less clean up on FG or BG
depending on the direction the knob is turned.
