NewTek TriCaster 8000 - Manual (Page 497)

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Consider what happens if you gradually raise the brightness control on your
television. Beyond a certain point (and unlike claims made for laundry detergent)
your whites do not become whiter. They can’t – the upper limit (white) is firmly
fixed. Instead, parts of the image that are nearly white are boosted, eventually also
becoming white. Meanwhile, black portions of the picture are tending towards gray.
Since white cannot become whiter, and black has become gray, we could say that the
dynamic range of the image has been narrowed. The net result is a less vibrant
image.
The same thing is true for video from your cameras. If the black and white levels
from the camera are incorrect, you are effectively losing either shadow or highlight
detail. For this reason, the first thing many do is calibrate their camera for correct
levels.
W AVEFORM M ONITOR
From days of old, for video engineering purposes the scale between black and white
was defined in IRE units (IRE being an acronym for “Institute of Radio Engineers”).
White was pegged at 100 IRE. For PAL (and NTSC-J) countries, black was defined as
0 IRE. For NTSC lands, black properly sat at 7.5 IRE.
Thankfully, the day of strict adherence to these analog video concepts has virtually
disappeared. Today, confirming that the black and white levels your camera is
sending TriCaster are correct is as simple as sending first black, and then white (or
the brightest past of your scene, and reading values from the scale alongside
TriCaster’s Waveform scope.
Hint: TriCaster automatically compensates for the traditional 7.5 IRE black (also known
as “setup” and “pedestal”) in SD format NTSC sessions.
Connect your camera to the correct TriCaster input, block the lens so it receives no
illumination, and check the level shown in the Waveform monitor. Generally, it
should be 16 on the 8bit scale.
To check white, use either the brightest part of your scene or a white card, ensuring
that it is evenly illuminated with the same lighting your main subject will receive.
Move in or zoom to fill the viewfinder with this, and confirm that the Waveform
monitor is showing 235 on the same scale. Otherwise, you might try using your