Prior to the start of calibration, PC-DMIS sets the exposure and gray sum values to the following:
Exposure: 300
Gray Sum Min: 10
Gray Sum Max: 300
These are the settings that work best for most calibration scenarios. Once the calibration finishes, PC-DMIS restores your original exposure and gray sum values (from before calibration). While gray sum values of 10, 300 are often appropriate for calibration, values of 30, 300 are typical for normal scanning.
Also, the default exposure value of 300 is often not sufficient in rare lighting conditions (such using a V4i with sodium lighting). If PC-DMIS has difficulty accepting the arcs during the calibration process, you may need to raise the default calibration exposure value to 400 or so. In these cases, modify the PerceptronDefaultCalibrationExposure registry entry located in the NCSensorSettings section of the PC-DMIS Settings Editor. For details, see the PC-DMIS Settings Editor documentation.
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Laser Probe Toolbox: Laser Pixel CG Locator Properties tab