Fisheye StereoCalibrate rms error

edit

Stereo Camera has a 107°H wide angle lens with a focal length of 2.9mm. I have calibrated both the camera's individually using

fisheye::calibrate(objectPoints, imagePoints, imageSize, camMatrix, distCoeffs, _rvecs, _tvecs, cv::fisheye::CALIB_CHECK_COND | fisheye::CALIB_FIX_SKEW | fisheye::CALIB_RECOMPUTE_EXTRINSIC); and the rms error for individual calibration is below 0.5

After undistorting the images obtained using the camera and distortion coefficients, the Stereo calibration using the below method is done. The rms error is around 2 to 4 most of the time. Any changes to be done or flags to be added.

fisheye::stereoCalibrate(objectPoints, LeftimgPoints, RightimgPoints, CL, DL, CR, DR, ImgSize, R, T, fisheye::CALIB_FIX_INTRINSIC + fisheye::CALIB_FIX_PRINCIPAL_POINT);