Christie M-Series User Manual page 66

Section 3: Operation
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.
• AUTO COLOR ENABLE:
When a checkmark is present, selecting a specific black level or drive to adjust will automatically enable the
corresponding color in the display. Delete the checkmark to see all colors, or to enable a different specific color
through the Color Enable control.
• CLAMP LOCATION:
Brightens the image produced from certain high-resolution high-frequency graphic sources. The projector
automatically selects the best clamp location for most sources. Use the normal Back Porch location if the
image is either sufficiently bright or overly bright. Select Sync Tip if the image appears unusually dim, if there
are horizontal streaks across the image, or if there is significant color drift. This moves the clamping pulse
from the normal back porch location (which is likely too short) to the tip of the horizontal sync pulse. Tri Level
is typically needed for an HDTV source.
• INPUT PEAK DETECTOR:
A tool to assist with defining individual input levels, enabling you to accurately set the Input Levels for any
particular source with the appropriate image. Enabling the Peak Detector activates a special operating mode for
detecting only pixels that are considered black or white—all other levels are displayed as a mid-level gray.
When used with a smooth grayscale pattern in which black and white are known to be at opposite edges of the
image, you can watch these isolated areas while adjusting individual black levels and input drives until both
black and white edges are just visible and distinguished from neighboring pixels. Images from this source will
then display correct blacks and whites without crushing. See
Peak Detector (RED EXAMPLE
1. Display a 16 level grayscale test pattern from the desired external source, and enter a checkmark in the
Input Peak Detector checkbox. NOTE: The Input Peak Detector will initially render the grayscale as a
uniform gray field before adjustment or extreme crushing.
2. Display one primary color. NOTE: Select Auto Color Enable to ensure the correct color is displayed for
each setting.
3. For the current color, adjust its corresponding Black level slide bar just until a single band of black appears
at one edge of the screen. This band represents the first band of the grayscale pattern, which should be
100% black.
4. With the same color still active, adjust its corresponding Input Drive slide bar just until a single band of
color appears at the opposite edge of the screen. This band represents the last band of the grayscale pattern,
which should be 100% white (or the current color, if a certain color is enabled).
5. Check the black band and adjust the black level slide bar if necessary. NOTE: Adjusting the black levels
affects the gain. Only adjust when necessary.
6. Repeat Steps 3-5 with the two remaining primary colors. When each primary color shows one optimized
black band and white (or colored) band, the input levels for this source are correctly set. Upon exiting the
Input Levels menu, the Peak Detector checkbox will clear.
3-26
SHOWN).
Figure 3-29 - Adjusting Input Levels Using the
M-Series User Manual
020-100009-02 Rev. 1 (04-2009)