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Camera Operation
2.
Setup the camera to capture a uniform dark image. Black paper with no illumination
and the camera lens’ iris closed to minimum can provide such a dark image. Or cover
the lens with a black lens cap.
3.
Click on
Acquire Black Image
. The flat field calibration tool will grab video frames,
analyze the pixel gray level spread, and present the statistics. The desired black
reference image should have pixel values less then 20. If the results are acceptable,
accept the image as the black reference.
4.
Setup the camera to acquire a uniform white image (but not saturated white). Even
illumination on white paper can be used, with a gray level of minimum of 128 (8-bit
mode). It is preferable to prepare for the white level calibration step before starting
the calibration procedure (see the previous section for information).
5.
Click on
Acquire White Image
. The flat field demo will grab video frames, analyze the
pixel gray level spread, and present the statistics. The captured gray level for all
pixels should be greater than 128 but not saturated. If the histogram shows a good
grab accept the image as the white reference.
