This is for stereo vision, structure-from-motion computations and so on (i.e. figuring out the geometry of what you're looking at from photos). Every lens that

This is for stereo vision, structure-from-motion computations and so on (i.e. figuring out the geometry of what you're looking at from photos). Every lens that is manufactured is slightly different, and has a slightly different ray-in-space to pixel mapping that these tools help you obtain.