I plan to calibrate an iPhone camera using OpenCV, the normal way using a checkerboard pattern. However, I am not sure if the pinhole camera model applies to iPhone cameras too!?
I believe iPhone cameras support optical zoom to some extent; however, I am not sure if this makes them not to be pinhole cameras. In other words, can optical zoom cameras be calibrated using OpenCV? Are they still considered to be pinhole cameras? If not, can we cope with the challenge by calibrating for a specific zoom value?
You worry about zoom but you also need to worry about focus. And any image stabilization.
Fix all those. Then the pinhole model applies and the calibration can be valid (all the usual pitfalls during calibration...).
This goes for any camera and lens setup.