LYNX Manual RA02
2.10
DYNAMIC SIGNAL-TO-NOISE CORRECTION
As was described in the section 2.7 (Gain and Offset), the reference black level on
each CCD output fluctuates around 0V – Figure 2.52. The AFE offset correction
works on the entire image and if there are noise fluctuations on a line level, the
AFE is not capable of correcting them. The camera has a built in dynamic signal-
to-noise correction feature to compensate for this effect. In the beginning of each
line the CCD has several back (masked) columns. The dark level is sampled over
several of these masked pixels and the average black level floor is calculated for
this line. This floor level is then subtracted from each incoming pixel from this
line.
video output
0 V
signal level
dark level
masked
pixels
exposed
pixels
corrected
signal level
Figure 2.52 - Dynamic Signal-to-Noise Correction
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