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Gain and Offset

uEye Camera Manual Version 3.80

Gain and Offset

Gain

In digital imaging, a voltage proportional to the amount of incident light is output by the sensor. To increase image brightness and contrast, this signal can be amplified by an analog gain and offset before the digitizing process. The results of analog signal processing are usually better than the results of digital post-processing.

Analog amplification of the read-out pixel values increases overall image brightness and contrast. Depending on the sensor type, a global gain value for all pixels (master gain) or a separate gain value for each color (RGB gain) can be set.

Hinweis

Note on using sensor gain

A signal gain will also result in a noise gain. High gain settings are therefore not recommended.
We suggest the following gain settings:

1.Enable the Gain boost function (is_SetGainBoost()).
2.If required, adjust the gain setting with the master gain control.

Hinweis

Note on the linearity of sensor gain

On uEye cameras, you can set the gain factor in increments from 0 to 100. These increments are not graduated linearly throughout the range due to the sensor. The increments will typically be greater in the upper range than in the lower range.

The maximum gain factor settings also vary from sensor to sensor.

Offset

Every digital image sensor has light-insensitive cells next to the active image area. These dark pixels are used to measure a reference voltage (black level) which is subtracted from the image signal. This compensates thermally generated voltages on the sensor which would otherwise falsify the signals.
Normally, the sensor adjusts the black level automatically. If the environment is very bright or if exposure times are very long, it may be necessary to adjust the black level manually.


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