A frequently used method for camera imaging performance evaluation is that based on the ISO standard for resolution and spatial frequency responses (SFR). This standard, ISO 12233, defines a method based on a straight edge element in a test chart. While the method works as intended, results can be influenced by lens distortion due to curvature in the captured edge feature. We interpret this as the introduction of a bias (error) into the measurement, and describe a method to reduce or eliminate its effect. We use a polynomial edge-fitting method, currently being considered for a revised IS012233. Evaluation of image distortion is addressed in two more recent standards, ISO 17850 and 19084. Applying these methods along with the SFR analysis complements the SFR analysis discussed here.
Peter D. Burns, Don Williams, "Camera Resolution and Distortion: Advanced Edge Fitting" in Proc. IS&T Int’l. Symp. on Electronic Imaging: Image Quality and System Performance XV, 2018, pp 171-1 - 171-5, https://doi.org/10.2352/ISSN.2470-1173.2018.12.IQSP-171