I'm taking pictures of little surfaces (5 x 5 Millimeters) in an experimental setup with an ids camera that contains a cmos sensor. Afterwards the pictures are split into the 3 color channels (red, green, blue) for further processing.
Before we started evaluating the pictures, my boss asked me to find out how different settings of the camera affect the pictures that are taken. The camera parameters allow for individually setting the gains for the overall brightness, as well as for every individual color (red, green blue). Any of these gains is said to take place inside the camera (analog gain, according to the manual), not in the software.
We then observed something we don't understand, maybe somebody around here can help: Whenever we changed the settings of an individual color channel (for example, the gain for the green signal), the value of this signal changed in a proportional way. So far soo good. Bad thing is: The other 2 channels (which we expected to not be affected at all) reduced their values significantly throughout enlarging the gain for the green channel.
Can somebody tell us, why that is the case, wether it is a usual behaviour, or how we could stop the signals for red and blue being affected by the gain for the color green?
Additional information: White-balance is turned off (this setting enables me to adjust the individual color gains in the first place). The camera Model is "UI-3280CP", Version "C-HQ" (Color - High Quality) by "IDS", the sensor is a global-shutter cmos sensor called "IMX264".
Additional Information: The decrease in the colors "blue" and "red" stopped as soon as the color green got into saturation (reached the value 255):