Christie M Series User Manual Download

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M Series User Manual

020-100009-05 Rev. 1 (09-2010)

Section 3: Operation

Good RGB or input levels—that is, the

drives

and

black levels

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.

For a source exhibiting overly high black levels (typically caused by a noisy source causing black level spikes)
use the

Input Levels

menu (shown above). These adjustments, serve as a calibration process compensating for

differences in sources and cabling, to perfect the source image input levels and eliminate the “overshoot” and
“undershoot”.

NOTES: 1)

Input Levels are of limited use with digital signals, but do offer some ability to tweak

poorly mastered source materials.

Input levels apply for the current source only, but for any color

temperature used.

Assuming that color temperature has been set up based on the internal test patterns, you

can then set up input levels for a given source so that it matches the color temperature of the internal test
patterns.

•

AUTO INPUT LEVEL

Use 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
black levels (black) that would cause “crushing” of light and dark colors in the image. After entering a
checkmark, wait for the six slide bar values to stabilize, then delete the checkmark and exit. The Auto Input
Level is automatically turned off upon exit from the

Input Levels

Menu.

•

BLACK LEVELS AND DRIVES

To check your image levels and adjust these controls:
1. Ensure overall “Contrast” and “Brightness” settings are both set to near 50.

NOTE

Not required for

“Auto” adjustment.

ONTRAST

= 50 (approx.)

RIGHT

= 50 (approx.)

2. Check the color temperature setup using an internal greyscale test pattern, making sure to obtain a neutral

greyscale.

NOTE:

Not required for “Auto” adjustment.

3. Confirm that you are using input on an Analog BNC card or a Dual Link DVI card. Input Levels are not

applicable for sources going through the decoder. A greyscale is recommended.

4. 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. Enable “Auto” in the

Input Levels

menu. Wait for all six values to

stabilize. Alternatively, do not use “Auto”—reduce black levels manually instead. Judge by eye and
change one or more of the six levels as necessary to obtain proper blacks and whites. You may want to see
only a certain color while adjusting—use the

Auto Color Enable

option (described below).

5. Delete the “Auto” checkmark and leave the

Input Levels

menu.

IMPORTANT:

Do not use Input Levels to adjust color temperature.

This will distort contrast and

brightness functions as well as color temperature.