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Guldini
March 9, 2009, 16:14:09
Hi Folks,

I have a DMK 31AU03.AS.
I want to use maximum dynamic range therefore I choose the lowest gain that provides as much of the full well capacity as possible.
Two problems come up:

1. There are no data available about the conversion rate of electrons to ADUs vs the gain setting. I tried to figure out by shot noise measurements and get roghly 60 e-/ADU at lowest gain to appx. 1 e-/ADU at highest setting. Does it sound reasonable ? Would be nice know the real gain in order to adjust the setting low enough to get the full dynamic range and high enough to avoid pixel saturation (as it can be seen clearly for the lowest gain)

2. Why is it not possible to enhance the display without converting the data ?
The more gain or gamma I add to the data the more dynamic range I loose.
I would like to apply gamma and brightness after stacking and aligning the images. But if keep the gain low it is difficult to "see" the lower bits on the screen, although they appear in the histogram.
I am sure a scaling based on the LUT only would extend the capabilities of the cameras for astronomical imaging.

regards
Guldini