How to Evaluate Checkerboard Calibration Target Accuracy: 4 Numbers That Matter
A supplier’s inspection report is the only way to trust a calibration target you can’t easily measure yourself, yet most reports mix real fabrication error with the mounting offset and rotation from the measurement stage. The two kinds of accuracy (position vs spacing), the four numbers that matter (pass rate, maximum radial residual, standard deviation, 95th percentile), why Kabsch rigid-body alignment is non-negotiable, a worked example, and five red flags when reading a supplier’s report.