7. Advanced
The same absolute black and white level for the three colors allows 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 also explains why each input
balance setting is linked to a particular source and thus saved in the image
fi
le).
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 considered source must be able to generate a white signal, ideally a 100% white (background) full screen pattern
2.
the considered source must be able to generate a black signal, ideally a 100 % black (background) full screen pattern
A
B
Image 7-30
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 black balance can be done automatically with
Automatic Black level
.
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 a black-and-white checkerboard pattern where the white
blocks will be used for white balance and the black blocks for black balance.
Image 7-31
How to set Automatic Black level ?
1. Press
MENU
to activate the Tool bar
2. Press
→
to select the
Image
item
3. Press
↓
to Pull down the
Image
menu
4. Use
↑
or
↓
to select
Input balance
5. Press
→
to pull down the menu
6. Use
↓
or
↑
to select
Automatic Black level...
68
R59770121 NH-12 04/05/2011
Summary of Contents for Galaxy NH-12
Page 1: ...NH 12 User Guide R9010610 R59770121 06 04 05 2011...
Page 8: ...Table of contents 4 R59770121 NH 12 04 05 2011...
Page 10: ...1 Introduction 6 R59770121 NH 12 04 05 2011...
Page 16: ...3 Installation guidelines 12 R59770121 NH 12 04 05 2011...
Page 54: ...5 Setup 50 R59770121 NH 12 04 05 2011...
Page 56: ...6 Getting started 52 R59770121 NH 12 04 05 2011...
Page 93: ...7 Advanced Image 7 68 Image 7 69 Image 7 70 R59770121 NH 12 04 05 2011 89...
Page 139: ...7 Advanced Image 7 147 Image 7 148 Image 7 149 Image 7 150 R59770121 NH 12 04 05 2011 135...
Page 162: ...7 Advanced 158 R59770121 NH 12 04 05 2011...
Page 174: ...8 Maintenance Image 8 24 Installing the rear cover step 5 170 R59770121 NH 12 04 05 2011...
Page 184: ...9 Troubleshooting 180 R59770121 NH 12 04 05 2011...
Page 188: ...Glossary 184 R59770121 NH 12 04 05 2011...