keep distance while fov is changing


I’d like to keep distance between camera and specific object while camera’s fov is changing with perspective lens.
In order to implement ‘vertigo’ effects.

Calculating proper delta distance is my problem.
Any ideas?

i guess it would be easier to work witih the focal length in your case.
if you keep a constant filme size you should be able to double or half both, object distance and focal lenth while keeping the object same-sized on your screen. fov is possible to but no need to do heavy math if panda can do it for you :slight_smile:

if your fov angle is alpha, the distance between camera and object d then:
d=1/tan(alpha/2) for keeping it same size