Christie roadie 25k User Manual page 89

Good RGB or input
levels—that is, the drives
and blacklevels for each of
the three colors, red, green
and blue—ensure that
images from analog sources
other than decoded video
have maximum contrast
without crushing black or
white. By default (and in an
"Auto Setup"), the projector
automatically determines
the best input levels by
monitoring image content and adjusting the controls appropriately—further
adjustment is typically not required to obtain proper blacks or whites. NOTE: This
automatic adjustment requires at least 6-12 consecutive white pixels in the image.
Without these pixels, input levels may produce skewed colors, particularly in non-
video images.
However, for a very unusual source exhibiting one or more overly high blacklevels
(typically caused by a noisy source causing blacklevel spikes), an experienced user
may prefer to use the Input Levels menu (shown above). These adjustments, which
together serve as a calibration process compensating for differences in sources and
cabling, enable an experienced user to perfect the source image input levels and
eliminate the "overshoot" and "undershoot". Note that Input Levels are of limited use
with digital signals, but do offer some ability to tweak poorly mastered source
materials.
Keep off for virtually all sources (default). Temporarily enter a
AUTO INPUT LEVEL –
checkmark only if you are an experienced user and you have an unusual source that
you feel needs further color temperature and/or input level adjustment. This
compensates for incoming out-of-range drives (white) and blacklevels (black) that
would cause "crushing" of light and dark colors in the image. After entering a
checkmark, wait for the six slidebar values to stabilize, then delete the checkmark
and exit. Auto Input Level should be automatically turned off upon exit.
BLACKLEVELS AND DRIVES -
1. Make sure overall Contrast and Brightness are both set to near 50.
NOTE: Not required for "Auto" adjustment.
•
Cont
•
2. Check the color temperature setup using an internal grayscale test
pattern, making sure to obtain a neutral grayscale. NOTE: Not required
for "Auto" adjustment.
3. Confirm that you are using an analog source not connected to
, as Input Levels are not applicable for digital sources or sources
INPUT 4
going through the decoder. A grayscale is recommended.
4. If the blacks and/or whites appear OK, input levels do not need
adjustment. If black levels are too high (and/or whites are too low, which
is rare), you likely have a noisy source that is producing skewed input
levels. Continue with Step 5.
To check your image and adjust these controls:
= 50 (approx.)
= 50 (approx.)
OPERATION
INPUT 3
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