SVS-Vistek SHR 10GigE, Руководство пользователя

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The amount of dark current in these areas is used to adjust the offset (see "Off-
set" below ).
For calculating image sizes, the maximum camera resolution is determining max-
imum image resolution, refer to the specifications of the camera model).
5.1.3 Offset
For physical reasons the output of a sensor will never be zero, even the camera is
placed in total darkness or simply closed. Always there will be noise or randomly
appearing electrons that will be detected as a signal (dark noise: noise generated
without light exposure).
To avoid this dark noise to be interpreted as a valuable signal, an offset will be
set.
Fig.: 5-2: Dark noise cut off by the offset
Most noise is proportional to temperature. To spare you regulating the offset every
time the temperature changes. A precedent offset is set by the camera itself. It ref-
erences certain pixels that never were exposed to light as black. So the offset will
be set dynamically and conditioned to external influences.
The offset can be limited by a maximum bit value. If higher values are needed, try
to set a look up table.
INFO For multi-tap CCD sensors, the offset can be altered for each tap separately.
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