Vidikron Vision 150 - Manual (Page 70)

Installation
56 Vision Model 140/150 Installation/Operation Manual
PRE
L
IMINAR
Y
• Clipping Detector: The Clipping Detector is a tool to assist with defining individual input
levels, enabling you to accurately set the white balance for any particular source with the
appropriate image.
Enabling the Clipping 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 and white levels 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.
Figure 3-21. Adjusting Black Levels and White Levels Using the Clipping Detector
1. Display a 16-level grayscale test pattern from the VHD Controller.
2. Enter a checkmark in the Clipping Detector checkbox.
3. Display one primary color.
4. For the current color, adjust its corresponding “Black Level” slidebar 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. Do not adjust too far.
5. With the same color still active, adjust its corresponding “White Level” slidebar 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). Do not adjust too far.
The Clipping Detector will initially render the grayscale as a uniform gray
field before adjustment or extreme crushing.
Selecting Auto Color Enable ensures that the correct color is displayed for
each setting.
4. Adjust corresponding
black level (red, green or
or blue) until one black
band appears.
5. Adjust corresponding
white level (red, green or
or blue) until one bright
band appears.
3. Choose one primary
color at a time.
1. Pre Calibration
2. Red Black Level 256
3. Red White Level 256
4. Green Black Level 256
5. Green White Level 256
6. Blue Black Level 256
7. Blue White Level 256
8. Auto Color Enable
9. Clamping Back Porch
0. Clipping Detector
Color Enable Red
White Balance
Note