Basler daA1280-54bc, Руководство пользователя

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Features AW00136902000
116 Basler dart BCON
11.11.3 Gain Auto
Gain Auto is the automatic counterpart to manually setting the Gain parameter. The gain auto
function automatically adjusts the Gain parameter value within set limits until a target brightness
value for the pixel data is reached.
The gain auto function can be operated in the Once and Continuous modes of operation.
The gain auto function and the exposure auto function can be used at the same time. In this case,
however, you must also set the Auto Function Profile feature.
For more information about

setting the gain manually, see Section 11.2 on page 83 .

the Auto Function Profile feature, see Section 11.11.6 on page 119 .
Lower and Upper Limits
The limits within which the camera will adjust the Gain parameter are defined by the
AutoGainUpperLimit and the AutoGainLowerLimit parameters.
Example: You set AutoGainLowerLimit to 2 and AutoGainUpperLimit to 6. During automatic
adjustments, the Gain parameter value will never be lower than 2 and never be higher than 6.
Target Value
When the gain auto function is enabled, it adjusts the gain until a target brightness, i.e., an average
gray value, is reached. You can set the target value using the AutoTargetBrightness parameter.
The parameter value range refers to the theoretically maximum available range of gray values for
the set pixel format.
Example: If an 8-bit pixel format is set, the maximum gray value is 256. Therefore, a parameter
value of 0.5 corresponds to a gray value of 128.
The target value calculation does not include gamma correction. Depending on
the gamma correction value set, images output by the camera may have a
significantly lower or higher average gray value than indicated by the
AutoTargetBrightness parameter value.
For example, if you set the pixel format to YCbCr422 and AutoTargetBrightness to
0.5, images output by the camera will have a higher average gray value than 128.
This is because an additional sRGB gamma correction value is applied after the
target value calculation has been performed.
For more information about gamma correction, see Section 11.4 on page 85 .