Is this even possible? Or does blender only support one focal length for x and y? And is it possible to set the focal length in pixels instead of mm? Because to set it in mm I would need to know the width of the image sensor, which I don't have. I am trying to model a real camera which I calibrated and the calibration software gives me fx, fy and the principal point I could set the principal point, but I'm still stuck with the focal length.

  • $\begingroup$ I believe this is NOT possible but Im still interested about the reason You need this. $\endgroup$ – Jan Matys Sep 26 '18 at 14:22
  • 1
    $\begingroup$ I think you are confusing something. Please see en.wikipedia.org/wiki/Focal_length One camera lens can only have one focal length at a time. It cannot be different in different axis - this does not make sense. It is measured in millimeters. Setting it in pixels would not make any sense as well since pixels do not represent any actual distance in the scene. $\endgroup$ – Martin Z Sep 26 '18 at 14:24
  • $\begingroup$ I thought so too, but you can check here: ksimek.github.io/2013/08/13/intrinsic under focal length it explains why it makes sense to have these seperate. Setting it in pixels is very common, because a lot of calibration software for calibrating real cameras gives you the focal length for x and y in pixels and I would like to model a real camera. $\endgroup$ – Hakaishin Sep 26 '18 at 14:28
  • $\begingroup$ Btw does it make sense to specify the focal lenght in mm and the fov? it doesn't right it's either or? $\endgroup$ – Hakaishin Sep 26 '18 at 14:41

Your Answer


Browse other questions tagged or ask your own question.