Dalsa SG-10-01k80 User Manual page 65

Spyder3 GigE User's Manual
To optimize camera performance, digital signal processing should be completed after any
analog adjustments.
1.
2.
3.
4.
Analog Signal Processing: Setting Analog Gain and Offset
All analog signal processing chain commands should be performed prior to FPN and
PRNU calibration and prior to digital signal processing commands.
Setting Analog Gain
Purpose:
Syntax:
Syntax Elements:
Notes:
Example:
Related Commands:
Calibrating Camera Gain
DALSA
PRELIMINARY
Fixed pattern noise (FPN) calibration (calculated using the
subtract away individual pixel dark current.
The digital offset ( command) enables the subtraction of the "artificial" A/D
s do
6 4 H
offset (the analog offset) so that application of the PRNU coefficient doesn't result in
artifacts at low light levels due to the offset value. You may want to set the
if you are not using FPN correction but want to perform PRNU correction.
Photo-Response Non-Uniformity (PRNU) coefficients (calculated using the
commands) are used to correct the difference in responsivity of individual pixels
c pa
6 7 H
(i.e. given the same amount of light different pixels will charge up at different rates)
and the change in light intensity across the image either because of the light source or
due to optical aberrations (e.g. there may be more light in the center of the image).
PRNU coefficients are multipliers and are defined to be of a value greater than or
equal to 1. This ensures that all pixels will saturate together.
Background subtract (
s sb
6 8 H
used to increase image contrast after FPN and PRNU calibration. It is useful for
systems that process 8-bit data but want to take advantage of the camera's 12 bit
digital processing chain. For example, if you find that your image is consistently
between 128 and 255DN(8 bit), you can subtract off 128 (
multiply by 2 (
ssg 0 8192
Sets the camera's analog gain value. Analog gain is multiplied by
the analog signal to increase the signal strength before the A/D
conversion. It is used to take advantage of the full dynamic range
of the A/D converter.
sag t f
t
f
•
sag 0 5.2
c cg
7 2 H
command) and system (digital) gain (
) to get an output range from 0 to 255.
Tap selection. Use 0 for all taps or 1 to 2 for individual tap
selection.
Gain value in a range from –10 to +10 dB.
To return the current analog gain setting, use the command
or .
g cp g et sag
7 0 H 7 1 H
command) is used to
c cf
6 3 H
value
s do
6 5 H
or
c cp
6 6 H
command) are
s sg
6 9 H
) and then
ssb 2048
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