VWC-44
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Please note:
e
、
Banding effect in edge blending area is related to projector color setting and gamma curve. The
projector should have the same gamma setting and [Display Mode].
f
、
Please disable [Dynamic] color or [Brilliant] color function in the projectors. These function will
change gamma
curve based on the content and affect final edge blending image quality.
13.5.3 [Offset]: Black level uplift
If edge blending is performed under dark environment, due to light leakage in projector optical
system, user will see gray area in overlapped area. This gray area can’t be fixed by signal
processing. The only way is to uplift the black level in non-overlapped area to reduce the black level
difference. [Offset] function is to balance black level in the display under dark environment.
Left picture is to show projector light leakage
under dark environment. In overlapped area,
the offset value is the sum from two projectors.
Low contrast ratio projector will be more
serious.
Left picture is to show banding effect in edge
blending area.
This issue is related to many factors:
Screen: gain value under 1.5 is recommended
Projector: should be the same model with the
same gamma and Display Mode settings.
Usually DLP projector will get better result.
Signal content: To avoid pure color or pure
white color content. Multimedia is the best.
Overlap range: too small overlap range will be
easier to see banding effect. 15%-25% with
more than 40 cm is recommended. (XGA: 6-10
grids, FHD: 10-20 grids, each internal pattern
grid size is 32 pixels)
When adjusting black level, [Offset] value will be
applied to complete color range and reduce image
quality. [Offset] gamma adjustment can avoid this
issue and let [Offset] adjustment only affect black
level but not complete image.
