NewTek TriCaster 855 - Manual (Page 343)

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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.
WAVEFORM MONITOR
For video engineering purposes, the scale between black and white is defined in IRE
units (IRE being an acronym for “Institute of Radio Engineers”). White is pegged at
100 IRE. For PAL (and NTSC-J) countries, black is defined as 0 IRE. For NTSC lands,
black properly sits at 7.5 IRE.
Using TriCaster’s Waveform monitor (in the Live Desktop’s Preview Scopes tab), you
can actually see the IRE values for your video sources graphed on a vertical scale
(select the source on the Switcher’s Preview row).
Confirming that the black and white levels your camera is sending TriCaster are
correct is as simple as sending first black, and then white, and reading the value
from the scale.
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. For NTSC, it should be 7.5 IRE, for all
others, 0 IRE.
To check white, use a standard white card or even a sheet of white paper. Ensure that it is
evenly illuminated with the same lighting your main subject will receive, move or zoom to fill the
viewfinder with it, and confirm that the Waveform monitor is showing 100 IRE.
If not, you might try using your camera’s Auto White Balance feature with the white card – your
camera manual will provide instructions. Afterwards, check the black level again. Some more
professional cameras offer full manual controls for white balance and/or black level. Use these
as instructed to ensure your camera is providing the correct white and black levels.
Figure 261