Camera Operation
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Close the camera lens iris and cover the lens with a lens cap. Using CamExpert, click on the
grab button and then the histogram button. The following figure shows a typical histogram
for a Falcon2 grabbing a very dark image.
Figure 24 CamExpert histogram of a dark scan (8 bit output)
Important:
In this example, the
average
pixel value for the frame is close to black.
Also note that most sensors will show a much higher maximum pixel value due
to one or more "hot pixels". The sensor specification accounts for a small
number of hot or stuck pixels (pixels that do not react to light over the full
dynamic range specified for that sensor).
Verify bright image
Aim the camera at the PRNU reference. Using CamExpert, click on the grab button and then
the histogram button. Use the lens iris to adjust for a bright gray approximately around a
pixel value of 200 (for 8-bit pixels). The following figure shows a typical histogram for a
Falcon2 grabbing a bright gray image.
