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Step 3: Calibrate the
black level
(brightness) of your video source:
• Find a video test pattern for adjusting black level, e.g. the
Black Bar
pattern from AVIA DVD from
Ovation Multimedia
• Turn the
brightness
setting of
Crystalio II
down excessively so that you see the whole image as black
• Turn the
brightness
up until you can barely see the difference between the black background and the
slightly brighter black bar (in the AVIA test pattern)
Step 4: Calibrating the
white level
(contrast or peak white level) of your video source:
• Find a video test pattern for adjusting
white level
, e.g. the
Needle Pulse
from the AVIA DVD from
Ovation Multimedia
• Turn the
contrast
setting of
Crystalio II
up excessively so that you see the whole image as white
• Turn the
contrast
down until you can barely see the difference between the white background and the
slightly darker white bar
Step 5:
Repeat
step 3
to
step 4
until the brightness and contrast settings need not be changed,
and R/G/B Offset and R/G/B Gain settings of the video source are satisfactory
To calibrate all video sources, you must perform the above steps to all video sources.
Remember to reset
Crystalio II’s
video settings for each input before your calibration.
If you have two kinds of video source, which have different level and/or color balance, from a single input port
(for example a DVD player used for both NTSC and PAL discs); or you wish to have a selection of different
video setups available, you can do the calibration and store the video settings in different
Video Profiles
. Note
that
Crystalio II
has 10 different
Video Profiles
for each individual video input port. If you use both NTSC and PAL
video into an input you can program
DynamicVP™
to automatically load the appropriate video profile depending
on the input vertical refresh rate
Crystalio II
detects.
Tips for calibrating sources without test patterns
• If you don’t have a test pattern for adjusting black level, select a scene with lots of dark areas (for
example, a man wearing a black jacket in a dark night background), and adjust the brightness just as
in
step 3
above, using the black background and the near-black object instead of the bars test pattern
• If you don’t have a test pattern for adjusting white level, select a scene with lots of bright areas (for
example, a sunny sky with a little bit of cloud), and adjust the contrast just as in
step 4
above, using
the white background and the near-white object instead of the bars test pattern
4.6.3.3 CALIBRATING COLOR TO COMPENSATE FOR DISPLAY AND SOURCE
INACCURACIES
Color calibration in
Crystalio II
is designed for instances where displays and sources cannot be accurately
calibrated using their own controls. It is a way of compensating for inaccuracies in connected devices.
For calibrating your display devices, there are separate
RGB Gamma Correction
controls and a Color
control in the
Output
menu.
For calibrating your source devices, there are separate
RGB Gamma Correction
controls and a
Color
Temperature
control in the
Image
menu.
In order to see these controls it is necessary to select the
Advanced Option
under the
System
sub-menu
and turn
Advanced Option
ON
Ways in which we can check for color accuracy are:
1. Check that shades of grey are really neutral (equal levels of R, G and B).
2. Check that pure R, G and B are really pure.
Sometimes it is necessary for a color measurement tool to be used at the screen to determine accurate levels.
