Can I move my camera after intrinsic calibration?

Question

I have 2 camera settings where the extrinsic properties between the two cameras do not matter. Generally, I start my work by calibrating each camera intrinsically and then move on to image processing.

I was just thinking - since the intrinsic calibration gives me a camera matrix that contains information on focal length, optical centre etc, as well as the distortion coefficients. From my understanding, these parameters do not change as long as the camera lenses are not adjusted. Therefore, maybe I am able to move the cameras after all?

I am thinking maybe this idea comes from my shallow understanding of the camera calibration. Please share your opinions on this matter. Thanks!

Answer 1

Yes, you have the correct understanding of camera calibration.

A camera's intrinsic parameters do not change if you move the camera, that is what separates the intrinsic parameters from the extrinsic ones. As you point out, the intrinsic parameters may change if you adjust the lens. Careful: depending on the lens type, simply focusing could be such a change to the lens.

There may be small influences on the intrinsic parameters from moving the camera (as the camera is not perfectly rigid) or from changing surroundings (e.g. temperature), but they are small enough to be disregarded for most use cases.