4 Design and function
3DPIXA
CD40131 Version 1
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For shading correction the offline calculation is recommended.
Use an image of a moving white object.
Do
not
use a static white reference for shading correction.
Generated data sets may be stored to the hard disc of the PC. The stored data can be
transferred to the camera later on.
4.6
White balancing
In order to set the video values to optimal conditions, the 3DPIXA camera supports an
automatic adjustment of the internal gain values. A closed loop can be established which
enables an automatism of setting the white point stable in optimal conditions.
Fig. 9:
Closed loop control for white balancing
With the 3DPIXA camera, the area of an image can be defined as a reference, and the
reference values (target values) can be set separately for each channel.
White balancing can be applied in 2 different ways:
Single setup process:
For 3DPIXA, white balancing is a single setup process with a static white reference in
front of the camera during its installation (see chapter 6.12.1, p. 68).
For 3DPIXA dual, white balancing has to be performed for the master and the slave
camera separately.
Adjusting the camera continuously:
Adjusting the camera continuously during the scanning process in order to compensate
variations of light is not necessary under normal operating conditions for 3DPIXA.
