Christie Roadie HD+35K, User Manual

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Section 3: Operation
Roadie HD+35K User Manual 3-69
020-100340-02 Rev. 1 (01-2010)
3.12.2 Achieving Brightness Uniformity
What is Brightness Uniformity?
When used to refine screens already matched for their primary colors (refer to Section 3.12.1 Matching Colors
In Multiple Screens ) and overall light output, proper adjustment of Brightness Uniformity can create an
exceptionally smooth screen in which:
• No area of the screen appears more red, green or blue than another.
• No area of the screen appears brighter than another color and light output from one screen closely matches
adjacent screens.
• Color and light output from one screen closely matches adjacent screens.
Although the Brightness Uniformity control can be used for a stand-alone projector, it is particularly useful for
setting up and maintaining tiled images that form a cohesive display wall in which the color "cast" and light
output appear uniform throughout each image as well as throughout the entire wall. The procedure provided
here assumes a multiple-screen application.
Before You Begin
Read through the entire procedure before attempting to adjust Brightness Uniformity controls, and keep in
mind the following checklist of prerequisites and guidelines:
• Adjust colors first. Adjust the primary colors as described in the "Matching Colors in Multiple Screens"
procedure (above) before attempting to work with Brightness Uniformity . This ensures that primary colors,
color temperature, and maximized light output are all well matched from one screen to another. These
matches are needed before you can achieve good Brightness Uniformity results.
• Run for 100 hours. Light output and Brightness Uniformity can vary significantly during the first 100
hours of lamp use. For best results with new lamps, either set up Brightness Uniformity after this period, or
do an initial setup and re-check at 100 hours.
• Set lamp power . Make sure each " Lamp Power " setting is as high as possible for your application while
still maintaining a good overall match of light output from screen-to-screen. By nature, achieving a uniform
brightness will require a slightly reduced overall brightness-this reduction will help ensure that you have
enough range of adjustment when examining brightness variables more closely from screen-to-screen, and
will help prevent premature "maxing out" when trying to match to a certain color, zone or projector.
• Use a "User" color temperature . Always adjust Brightness Uniformity for a User color temperature
defined when you matched primary colors, and continue to use it for all sources displayed on the wall. Your
other color temperatures will not necessarily be matched from screen-to-screen.
• White Uniformity sliderbars . White Uniformity slidebar values may not always reduce to "0". Each
slidebar adjusts overall light output in a specific screen zone, but the value shown represents the current
setting for green in this zone. When other "hidden" values (red or blue) are lower than green, during
adjustment in the
White Uniformity
menu their values reaches "0" first, causing the slidebar to stop earlier
than expected.
• Judge by eye or use a meter . Good brightness uniformity can be achieved with either technique.
General Setup
1. Adjust primary colors (refer to Section 3.12.1 Matching Colors In Multiple Screens ) to ensure matched
overall color temperatures and light output between screens.
IMPORTANT
! Double-check that all WHITES and LIGHT OUTPUT are well-matched.