Lumagen Radiance XS-3D - Manual (Page 36)

Section 7 – Calibration
RadianceXS rev 091211 28
Section 7 - Calibration
Your theater system needs to be calibrated. To brighten the image in the show room, most display
manufacturers intentionally change the display calibration away from industry standards. Unfortunately most
displays do not have the controls necessary to undo these errors. Correcting these intentional errors, and
other unintentional errors, so the image appears as the producers intended, is a primary function of the
Radiance. The Radiance has a host of features dedicated to this task.
It is recommended that a professional calibrator be hired to perform the calibration. An experienced
professional calibrator has the necessary tools and experience to extract the best performance from your
theater. However, you can improve your picture without hiring a professional if you prefer. You will need to
learn how to use the Lumagen test patterns, or use a calibration disc (such as AVIA, Digital Video Essentials,
or Spears & Munsil High-Definition Benchmark). Then you need to spend time learning how various
calibration controls interact and how they affect image quality.
To understand Radiance calibration, it is important to note that setup and calibration parameters are split
into “input memories” and “output configurations.” Input memories are for source specific setup and
calibration. Output configurations deal with display setup and calibration. These are covered elsewhere in
this manual.
It is recommended that the internal Lumagen test patterns be used to calibrate the output configuration.
This will assure that any variance between sources (size, color or levels) do not affect the calibration of the
display. Note that some professional calibrators prefer to use a test pattern generator for all calibration
functions. This method can also work well. After the display has been calibrated, differences between inputs
can be calibrated using test patterns played on the source devices or test pattern generators.
The recommended Lumagen calibration sequence is shown below.
Set the display’s picture controls to neutral
•
Disable enhancement features on the display. Features such as sharpness, DRC and certain color
mode settings do not live up to their advertising and can actually reduce image quality. In addition
the Lumagen enhancement features work best when the display is set to have it’s own
enhancement features disabled.
•
Select the display color temperature setting that is closest to the “D65” for white. This is often
referred to as “D65,” “warm,” or “cinema” color mode, but this varies between manufacturers.
Calibrate black and white levels using display controls
• To calibrate the black and white levels in the display, select the Lumagen contrast test pattern. Use
the right-arrow key to select the Contrast 1 (or Contrast 2) test pattern. The Contrast 1 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. The test pattern
command is:
MENU → Other → Test Pattern → Reference → OK
NOTE:
”L and R arrow” selects pattern group, “U and D arrow” adjusts IRE on some patterns, “2”
hides menu, “4” steps through patterns in group, “CLR” completely exits, “Ok” exits &
leaves pattern up. If exiting with “Ok” you can toggle between live video and the test
pattern with “Prev” and use “Alt” to jump back to the test pattern command.
To change the test pattern timeout MENU → Other → Menu control→ Timeouts → Test
pattern timeout → (Normal, Slow, Never)→ Ok
•
Adjust the black level using the display’s 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.
•
Adjust the white level using the display’s contrast control. Adjust so that the 96 IRE bar is still
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 if there is headroom above white.