Barco RLM G5I PERFORMER R9010320 - Manual (Page 81)

8. Image Menu
Black level setting : brightness
White level setting : contrast
The same absolute black and white level for the three colors allow the same reference for Brightness and contrast control of the
picture !
These two references also set the range in which the ADC will work for that particular source (this explains also why each input
balance setting is linked to a particular source and thus saved in the image file).
8.9.2 Adjusting the input balance
How can it be done ?
To balance the three color signals of a particular source there are conditions; in fact we must know the black and the white level of
the source i.e. :
1.
The source in question must be able to generate a white signal, ideally a 100% white (background) full screen pattern
2. The source in question must be able to generate a black signal, ideally a 100% black (background) full screen pattern
A B
Image 8-36
White balance : In the projector, we will set the contrast for each color until we get a 100% light output picture when projecting a
100% white image (image A)
Black balance : In the projector, we will set the brightness for each color until we get a 0% light output picture when projecting a
100% black image (image B).
The changeover from min to max is indicated by the apparition of bright spots also called “digital noise”
An alternative to a full screen White/black pattern is the standard gray scale pattern, the white bar will be used
for white balance and the black bar for black balance.
Image 8-37
R5976815 RLM G5I PERFORMER 02/06/2006 79