Thanks @crackwitz for your reply. I understand that zoom causes lots of problems for calibration. Currently the approximation go-to method for video with zoom involves accounting for zoom with focal distance but keeping the position of the camera fixed.
I went through OpenCV’s clibratecamera documentation many times and cannot find HOW to fix parameters like tvecs. Could you point me in the right direction?
that’s simply wrong.
you might have expected, this is some kind of ‘world’ position – very much NOT SO !
so again, it’s unclear, why you would want to ‘fix’ those (it’s impossible)
also, the rvecs/tvecs obtained from calibration are only useful to check the calibration. (they have NO meaning without checkboards later on …)
Thanks @berak , are they not defined with respect to the origin (0,0,0) of the coordinate system of the chessboard? That would essentially indicate the positioin of the camera, as -np.transpose(cv2.Rodrigues(rvecs))@tvecs.
In my case I have a video that was shot from the camera in the same position. But the camera is zooming and rotating. Only it’s position stays the same. I assumed that rvecs and tvecs were rotation and position of the camera and that’s why I wanted to keep tvecs constant and rvecs flexible. …