Dalsa ML-FM-16K07A Manual page 34

Object Pixel Setup for 20 µm, Encoder set at 19 µm. Forward Scanning
Can be corrected with 20 / 19 = 1.05 Line Spatial Correction
Object Pixel Setup for 20 µm, Encoder set at 21 µm. Forward Scanning
Can be corrected with 20 / 21 = 0.95 Line Spatial Correction
If there are several different camera angles and associated illumination configurations in the
inspection system, a single encoder pulse will not provide the correct timing for all the cameras.
For example, as the camera angle moves away from perpendicular, the image row spacing
increases. If the encoder resolution remains at that for perpendicular operation, many encoder
pulses will be too closely spaced, apparent row spacing will increase and the line spatial correction
will need to change. The Line Spatial correction feature can accommodate these potentially larger
encoder errors where the spatial correction value has an adjustment range from 0 to 1.5.
The following section details more aspects of using the camera at angles.
34 • Camera Performance and Features