Genie Color Series-GigE Vision Camera
Operational Reference
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Click the Auto White Balance button to have CamExpert adjust the RGB gain to achieve a realistic color cast
under the current lighting conditions. The auto white balance function should be executed again when lighting
conditions or color temperature change.
The CamExpert auto white function can work on a smaller ROI. Within the CamExpert acquisition window,
click and drag a ROI rectangle with the mouse left button. Having a ROI of an evenly illuminated non-saturated
image of a white or light gray surface may produce superior results.
The independent RGB gain controls, expressed in decibels (dB), range from 0db to 12db. Used for manual
white balance adjustments or specialty needs.
Individual RGB gains are multiplied by the overall Gain adjustment.
Gain and Black Level Controls
The Genie color series cameras provide gain and black level adjustments for the analog signal from each CCD
pixel, before the analog to digital conversion. The software gain and black level controls can make small
compensations to the acquisition in situations where the lighting varies and the lens iris can not be easily accessed.
Features and limitations are described below.
Gain is expressed in decibels (dB). Range from -6dB to +12dB in 0.1dB increments. Gain is a multiplication
factor to the analog signal (i.e. exposure) before digitization.
Note that a gain of 6dB is a multiplier of 2 (doubles the level).
Increasing gain increases the amplitude of the analog video signal but also increases the sensor analog noise
proportionately, before analog to digital conversion.
Note: Doubling gain does not necessarily double the digital data due to the Black Level Offset value as
described below.
Black level offset is applied to the sensor analog signal to shift the DC level of the video signal. Black level is
an additive offset to the analog video signal before digitization.
Black level offset increases the brightness of the video signal equally. Therefore any area of the video that is
black will brighten to some gray level as offset is increased.
Black level offset is expressed as a number ranging from -128 to 127. The offset is achieved as a change in the
analog signal from the sensor where a control number change of 1 is 1/16
th
of a DN (digital number) pixel
change. In other words, a control change of 16 is required for each change in pixel value, therefore a maximum
control value of 127 will cause a black pixel (00) to have a gray value of about 8.
