Christie DW6Kc, User Manual

Page: 59 / 177

Section 3: Operation
3-30 020-100001-01 Rev. 01 (04/07)
3. Confirm that you are using an analog source not connected to INPUT 3 or INPUT
4, as Input Levels are not applicable for digital sources or sources 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.
5. Temporarily enable “Auto” in the Input Levels submenu. 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 “Color Enable” option (described below).
6. 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 –
This option (formerly known as
sync tip
clamping
) can brighten the image produced from certain high-
resolution high-frequency graphic sources. The projector
automatically selects the best clamp location for almost all
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.
COLOR ENABLE –
Select which color or colors you want to see in the display, useful
while working with color temperature white levels or input levels.
NOTES: 1)
Input levels apply for the current source only, but for any color
temperature used.
2)
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.
PEAK DETECTOR –
The Peak Detector is 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 Figure 3.7.
Adjusting Input Levels Using the Peak Detector
: