Camera calibration profile for GoPro Hero 4 black

Can you redo the calibration using your monitor? Your printed checkerboard seems to be too small to have good results.

Thank you.

This should give better results:

{
  "distortion_coefficients": [ -34.703513, 329.153650, 0.001109, -0.000264, 74.790386, -34.435316, 319.704791, 166.905882, 0.000000, 0.000000, 0.000000, 0.000000, 0.000000, 0.000000],
  "intrinsic_matrix": [ 1733.287865,0.000000,1357.886809,0.000000,1733.987417,739.075408,0.000000,0.000000,1.000000]
}