User`s manual

Spyder 3 GigE User’s Manual
DALSA 03-032-10158-09
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for use only when FPN is negligible and FPN coefficients are set
to zero. Since this algorithm adjusts the analog gain, it also
affects FPN. If FPN is calibrated prior to running this algorithm,
FPN will be observable in dark conditions and an incorrect FPN
value will be used during PRNU calibration resulting in
incorrect PRNU coefficients.
This algorithm is more robust and repeatable than algorithm 1
because it uses an average pixel value rather than a number
above target. However, this algorithm is slower.
i
Peak target value in a range from 1024 to 4055DN. The target
value must be greater than the current peak output value.
Notes:
• Perform all analog adjustments before calibrating PRNU.
• This command performs the same function as the
cpp
command but forces you to enter a target value.
• Calibrate FPN before calibrating PRNU. If you are not
performing FPN calibration then issue the
rpc (reset pixel
coefficients) command and set the
sdo (set digital offset)
value so that the output is near zero under dark.
• The QuickCam software that ships with the Spyder 3 GigE
camera has a flat field correction wizard. For easy flat field
correction, use the wizard located on the Calibration tab.
Example:
cpa 1 600
Performing PRNU Correction to a Camera Calculated Value
Purpose: Performs PRNU correction and eliminates the difference in
responsivity between the most and least sensitive pixel creating a
uniform response to light.
Syntax
ccp
Notes:
• Perform all analog adjustments before calculating PRNU.
• Perform FPN correction before PRNU correction.
• If FPN cannot be calibrated, use the
91Hrpc command to reset
all coefficients to zero, and save them to memory with the
92Hwfc command. You can then adjust the digital offset (93Hsdo
command) to remove some of the FPN.
• Ensure camera is operating at its expected analog gain,
integration time, and temperature.
• Refer to
288HCalibrating the Camera to Remove Non-
Uniformity (Flat Field Correction)on page
289H71 for a
procedural overview on performing flat field correction.
• To save FPN coefficients after calibration, use the
94Hwpc
command. Refer to section
290HA3.1 Saving and Restoring
PRNU and FPN Coefficients for details.
• The QuickCam software that ships with the Spyder 3
GigE camera has a flat field correction wizard. For easy
flat field correction, use the wizard located on the