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3.3 Adjusting for Optimum Picture Quality
3.3.3 Input Adjustments—Video Sources
Video signal processing is an option; the display you are working on may not have this option. The
Input Level menu is different when a video sources is selected. Use a color bar pattern when making
these adjustments.
The video adjustment procedure is the same
whether the source is from the composite or
S-video connector, whether it is NTSC, PAL, or
SECAM.
When the selected source is composite or
S-video, the Input Level menu looks this:
Video Controls
Brightness
Contrast
Saturation
Hue
Video Track 001
Blue Only
Sample
R:xxx G:xxx B:xxx
Input Level menu
for video sources
Brightness adjusts the image for overall
light and dark
Contrast increases the different between
the light and dark parts of the image.
Saturation adjusts the amount of color in
the image.
Hue adjusts the tint of the images, making
them more green or more magenta.
1. In Source Select, choose Composite or
S-video.
2. Select NTSC, PAL, or SECAM as the
mode. (Mode selection is not automatic.)
3. Connect a video source to the composite
or S-video connector. The signal is
internally terminated in 75Ω. The loop-
thru output is buffered.
4. Display an all-black picture from the video
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127
127
127
127
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source. This should come from the actual
source that will be used for program
material, not from a test signal generator.
For DVD players, frame 50882 on
Reference Recordings, "A Video Standard"
test disk has this picture.
5. Highlight Brightness and adjust it with
the right-left arrows. Make the R, G, and
B values as close to 001 as possible and
keep the Brightness number as high as
possible.
• If the initial Sample values are greater
than 001, reduce the Brightness until
the first Sample value reaches 001.
• If the initial Sample values are 001,
increase the Brightness until all Sample
values are 002 or greater. Stop
increasing Brightness when the last
Sample value goes from 001 to 002.
• If Brightness is decreased while the
Sample values are at 001, the color
range for the displayed image will
decrease.
6. Display an all-white image. Frame 50823
on Reference Recordings, "A Video
Standard" test disk has this picture.
7. Set the Sample values for R, G, and B as
close to 254 as possible while keeping the
Contrast number as low as possible.
• If the initial Sample values are less
than 254, increase the Contrast until
the first Sample value reaches 254.
• If the initial Sample values are 254,
decrease the Contrast until all Sample
values are 253 or less. Stop adjusting
when the last Sample value goes from
254 to 253.
• If the Contrast is increased while the
Sample values are at 254, the color
range for the image will decrease.
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