Lumagen VisionDVI & VisionHDP - Manual (Page 14)

VisionHDP ™
User Manual and Installer Guide
© 2004-2007 Lumagen®, Inc. 11 Rev 1.14
Output Calibration:
• The interface between the Lumagen and display should be calibrated first. This is best
accomplished using the internal Lumagen test patterns to assure that any variance in a source
(either size or levels) does not affect the calibration. Later, differences between inputs can be
calibrated using the source devices. If grayscale is to be calibrated, a base line calibration
should also be done after setting black and white levels.
• To calibrate the black and white levels, select the Lumagen contrast test pattern (MENU →
MISC → TPAT → OK), then use the left-arrow key to select the contrast test pattern. This
pattern has two white rectangles and two black rectangles. In the dark areas, there are two
vertical bars – One at 4 IRE and one at –4 IRE. The white area has two vertical bars – one at
96 IRE and one at 104 IRE. Note that 0 IRE is reference black and 100 IRE is reference white.
Since –4 and 104 are outside the nominal black to white range, not all displays will show these
levels.
First adjust the display’s black level using the brightness control. Adjust so that the 4 IRE bar
is barely visible against the black background (0 IRE). There should be no visible difference
between the black background areas and the –4 IRE bar. This is a secondary indication verses
the 4 IRE bar, but can be useful in optimizing the black level in displays that support blacker-
than-black.
Next adjust the white level using the display’s contrast control. Adjust so that the 96 IRE bar is
barely visible against the white (100 IRE) background. If a display supports whiter-than-white,
the 104 IRE bar may be visible. This is not a requirement, but does show that there is some
additional headroom above white.
If either or both the 4 IRE and/or 96 IRE bars cannot be seen after adjusting the controls,
recheck that the appropriate output level has been selected.
• Grayscale and gamma should be calibrated at this point. Calibrating these parameters is an
essential part of the video calibration process. However, a trained technician using the
appropriate equipment must calibrate grayscale and gamma.
Grayscale calibration adjusts the “color of gray” so that the color “gray” adheres to the industry
standard D6500 point, at all levels from black to white. Most HDTVs, and projectors, are
intentionally miss-calibrated to maximize their brightness for the showroom. This calibration
step is necessary to correct this error, so the image appears as the producers intended.
Gamma is the response curve between black and white and also has an industry defined
standard that should be followed. Lumagen has developed a unique 11-point parametric
grayscale/gamma calibration feature, which allows both grayscale and gamma to be optimized
over the entire range from black to white, and not just at one or two points.
Lumagen strongly suggests that a qualified video technician be hired to do grayscale and
gamma calibration. A technician with the proper training and equipment must do the
grayscale/gamma calibration. Contact Lumagen for the service codes necessary to use the
grayscale and gamma calibration features.
• After completing the output calibration, copy the results to all configuration memories using the
following command:
MENU → IN → COPY → ALL → OK
• It is a good idea to save the configuration before proceeding. Use the SAVE command as
shown below:
MENU → SAVE → SAVE → OK