I read the section on this subject in the documentation for cameras where this occurs. I am curious to know if this skews measurements for speed, time or distance that are shown. In other words, if I am tracking the distance of a ball, is it actually different than being shown by the software as it gets to the edge of the visible screen due to curvature seen with barrel distortion?
- joan
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Yes, if the lens has a lot of distorsion, two distances with the same physical length will not be projected on the camera image identically.
For example, if your reference segment is in the center of the image, and you are measuring segments or speeds at the edges, the measured segments will be smaller than they should.
This affects length and speed.
What you can do is hold a chessboard right in front of your camera (perpendicular to the camera axis). You can then start to evaluate how serious the distorsion is for your camera.
I have not much data on the subject, maybe it is negligible for most sport application relatively to other sources of errors.
(for example, the error introduced when the plane on which measures are made is not perfectly perpendicular to the camera axis.)