Vision Research Phantom v1211, Руководство пользователя

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Phantom Ultrahigh-speed cameras Manual
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Gamma is the nonlinear relationship between signal
level and brightness output of pixels, (a small signal level
change at low voltage produces a larger variation in
brightness than the same change in level at high voltage).
A linear gamma would have the value of 1.0. The
camera’s default gamma setting is 2.2, which is a
standard compensation for most video monitors.
EI (Exposure Index) is a reference value for the ISO level
of the current shooting settings. A camera’s default EI
value is measured at the default gamma of 2.2. Increasing
the gamma will also increase the EI, and decreasing the
gamma to a minimum value of 1.0 will decrease the EI.
The EI can also be adjusted by the adjusting the EI value
itself, using the on-camera controls, as indicated here.
Increasing the EI adds gain to the video image, the more
gain that is added the more digital noise will be visible in
the resulting cine. Vision Research recommends maintain-
ing the EI as close to default as possible for best image
quality.
The Master black (Pedestal) parameter is used to
change the voltage level corresponding to black or to the
maximum limit of black peaks.
The gain can be adjusted in three separate color channels,
red, blue, and green.
The pedestal can be adjusted in three separate color
channels, red, blue, and green.
The gamma can be adjusted in three separate color
channels, red, blue, and green.
Master gamma
EI
Master black
Gain (R, G, B)
Pedestal (R, G, B)
Gamma (R, G, B)