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Operational Reference
Linea Lite GigE Series Camera
Figure 78: Sapera Color Calibration Tool Shortcut
Refer to the tool’s online help for information about generating coefficients.
Crosstalk Correction
The crosstalk correction algorithm in the camera is designed to remove the crosstalk in the green
row that occurs from the neighboring red and blue pixels. This crosstalk shows up as an odd/even
pattern in the green row as red and blue light affect alternating pixels.
Figure 79: Sensor pixel array.
Calibration
In most cases, the default calibration will remove most of the crosstalk. However, if the angle of
incident light with respect to the sensor changes, the crosstalk correction values may need to be
adjusted.
It is recommended to calibrate the crosstalk by using the following steps:
1.
Configure the camera with all corrections off (crosstalk, flatfield, color correction) and with
color interpolation set to basic.
2.
Capture a dark image, a red image under red illumination, and a blue image under blue
illumination.
3.
Subtract the dark image from the red image and the blue image, then measure the average
of the Gr and the average of the Gb pixels in the dark-subtracted red and blue images.
4.
On the blue channel of the dark-subtracted blue image, average all even-numbered pixels
and save as B (refer to Figure 79).
Gr1
Gb1
R1
B1
Gr2
Gb2
R2
B2
Gr3
Gb3
R3
B3
Gr4
Gb4
R4
B4