I have a computer-vision application I made to localize a robot in a room; the software has been in use for a while and is working fine.
When I calibrated the camera and got the intrinsics and lens distortion coefficients there was a lens protector on the lens, mounted on the robot's lid.
If I take off the robot's lid (and thus the lens protector) the localization solution becomes erratic and inaccurate, so I think the lens protector might be changing the distortion properties significantly.
Today the lens protector became detached and it was replaced shortly after. So now the calibration may no longer be valid and the localization solution is much more noisy.
Can a lens protector can greatly effect the distortion properties of the image, or can someone offer another explanation?
I intend to recalibrate and super-glue the lens protector down to the robot's lid, but I am curious if this is my problem, and if anyone else has encountered this with lens protectors.