Image criteria for barrel distortion calibration

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Hello all,

I am attempting to find a more concrete system of using OpenCV for barrel distortion correction.

My camera is to be mounted in such a way that it will not move during operation. Am I able to use only one image to correct barrel distortion? If not, what positions and how many are needed to have barrel distortion corrected? My image has definite keystone distortion as well. I know that people say to use at least 10 images but I am looking for a more professional procedure to properly calibrate using OpenCV.

Thank you!