68
•
Camera Operation
Figure 22. Spectral distribution of light source used during calibration of color cameras only. This corresponds roughly to a 5200
K color temperature.
How to do an FFC Setup in the Camera
CamExpert has a default timeout of 20 seconds per command, which is too
short for the FFC calibration to run fully. You can change the default timeout by
setting a command line argument in the short-cut:
•
Right click on the short-cut in the start menu and select properties.
•
Add –timeout 60 to increase the command timeout to 60 seconds (See
below)
•
Repeat for desktop short-cut
Figure 23: Setting the camera’s timeout value
The calibration is performed in two steps. The fixed offset (FPN) is determined first by
performing an averaging without any light. This calibration determines exactly how much
offset to subtract per pixel in order to obtain flat output when the sensor is not exposed.