vds 69871-01, Руководство по эксплуатации и техническому обслуживанию

Страница: 55 / 93

Marquee ACON Ultra Installation/Operation Guide
2-32 AU User Controls, Settings and Operation
wider than that of the projector
brightness
parameter. When beginning the process of adjusting test
point visibility settings, Set the two camera parameters as discussed previously (
gain
at 100%,
offset
at 50%) and then set the projector
brightness
at mid range (total brightness range is 0-255, so
midrange is 127). Adjust the projector
contrast
to obtain appropriate levels. After the results have
been calibrated, if minor adjustments are needed, the projector
brightness
can then be used to fine
tune the settings. Use the Test Current Level button to command AU to perform tests of the current
settings. After the current levels are tested, a score (0% - 100%) is generated for each color and a
composite score. Each of these scores must be above 50% for the current levels to be deemed
acceptable. Higher scores are preferred.
NOTE: During initial attempts to set the visibility settings, it is not necessary to achieve perfect
results; the visibility settings will be refined throughout the entire setup and calibration
process. A typical approach for the initial attempt is to use manual settings combined with
the AGC results and the Test Current Level button to make one test point as good as
possible. Then copy these settings to all other test points in the set.
The Automated Gain Control algorithm (or AGC) sweeps the enabled parameters through a defined
range to use a brute force method of identifying the best set of parameters. When sweeping through
multiple parameters, the sweeps are nested. Every step of the secondary parameters must be
examined at every step of the primary parameter.
For example: Consider an AGC calibration where only Contrast is enabled. The low and high ranges
are 40 and 50 respectively, and the step size is 10. AGC will analyze the images of the two settings
and be finished. Now consider that Camera Gain is enabled with its step size, low and high ranges at
25, 50 and 75 respectively. Now the AGC has four images to analyze as shown in the following table
Step Contrast Gain
1.
2.
40 50
75
3.
4.
50 50
75
Now consider enabling G2 for all three colors the following table indicates the number of steps
required of AGC. The settings for G2 we will use are 100, 1600, 1700 respectively for step size, low
and high range. The number of steps required to complete AGC has risen by the number of steps of
the new parameter times the number of colors required (2 steps * 3 colors) so now instead of 4 steps
to complete AGC, 24 are needed.