LQ-401CL
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Fig.19 Shading correction
The shading correction has two ways to compensate, flat shading correction and color shading
correction.
Flat shading correction (SDR=0):
Flat shading correction compensates red, blue, green and NIR signals to be flat output. The range of
compensation is within plus-or-minus 20% as compared the brightest signal level. It may not
compensate enough according to the lenses and/or lighting in use.
As the default, the data which is activated in the factory is stored.
Fig.20 Flat shading correction concept drawing
Note:
Depending on the optics and/or illumination used together with the camera, it may not
be possible to fully compensate for shading.
Operating procedure for individual R, G ,B and NIR channel shading correction:
1. Before making adjustment,
approximately 30 minutes of warm up is required.
2. Make sure the output signal is not saturated (<80% of full output is recommended)
3. Set command PGC=2 and SDC=2.
4. Set command SDR to 0 to initiate shading correction.
5. If desired, set command PGR to 0 to activate flat-field (pixel gain) correction to
correct for pixel response non-uniformity.
6. Again set SDR=0 after running the flat-field (pixel gain) correction
Shading caused by uneven illumination or transmission at the edges of the lens.
Pixel response non-uniformity will be superimposed on the output signal
