NewTek TriCaster 8000 - Manual (Page 499)

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As it happens, from the vectorscope point of view, neither black nor white properly
have any color saturation. Thus with the lens cap on (or with a white card filling the
viewfinder), the vectorscope should show only a small fuzzy trace at its center. If
the fuzzy dot is off-center horizontally or vertically, this would indicate that the
camera is incorrectly calibrated, actually tinting gray areas.
When the trace is off center, the direction and distance of the offset tells us what sort
of tint (and how much) is represented by the deviation. You may be able to use the
color controls at your camera to correct for this offset, or you can use the U Offset
and V Offset controls in TriCaster’s Proc Amp to do so (as always, source controls are
best). Adjustments to U Offset move the trace left or right, while V Offset changes
adjust its vertical position.
Let’s move on to a slightly more rigorous testing.
C.2.3 COLOR METRICS
At this point, we’ve assured ourselves that the signal from the camera is neither too
bright nor too dark, that its output falls within broadcast legal luminance limits, and
that the black & white part of the signal does not have an unwanted color cast.
We haven’t done anything yet, though, to assure our reds are red, not slightly
brown, or that our blues are not slightly green or magenta, etc. The Vectorscope can
provide much more specific information about your cameras color signal. Let’s see
how it can assist you to ensure your colors are accurate.
U SING C OLOR B ARS
You’ll no doubt have seen the familiar color bars used as a standard reference for
video signal calibration. Two examples are shown here. Figure 404 is an example of
the color bars used in NTSC countries, while Figure 405 is a PAL example, common
throughout European nations.