*On 02/08/2017 at 01:16, xxxxxxxx wrote:*

Hi!

I am developing a camera-tracking solution for stills in Rhino3D/Grasshopper, which optimizes camera position,rotation,focal lenght and optical distortion through minimizing the deviation of Points in a picture and their projected 3D-counterparts.

So far, it works really well, even with rather imprecise point positioning, but i was wondering wich mathematical model C4D uses to calculate optical distortion, which can be set with two values in the physical camera object.

Now i am using the Brown-Conrady model respectively the definition used in Zhang (https://en.wikipedia.org/wiki/Distortion_(optics)), but as there are different models to describe optical distortion, I would like to know the model C4D uses.

Then i could optimize the solution to fit best with the values i can tweak in C4D.

Any suggestions?

best regards,

flowolf