Hi, please excuse me if this is too off-topic but I hope to find some knowledgeable people here.
I have a camera (Panasonic FZ1000) with a fixed zoom lens with a shortest focus length of 25mm (eq. to full format).
Now I have bought a second hand wide angle adapter for a different make of camera. With this I can get to a focus length of 18mm. But the images aren’t sharp near the boundary.
Does anybody know about (references to) mathematical means to correct this.
I wouldn’t mind solving partial differential or integral equations numerically if this should be necessary.
I could even do some inverse computation of parameters of a given model.
A wide angle converter will not get you good quality unless it’s matched to the lens, like the Ricoh GR and its GW-3. Plus, the FZ1000 is wider than most to start.
You can only correct certain aberrations after the fact: distortion (lossless, effectively) and lateral chromatic aberration (nearly lossless). Others require deconvolution which amplifies noise and has computational precision issues and has ringing and you have to crop the edge…
it will correct distortion but there is little you can do about lens distortion at the edges. There is a reason why very high quality fish-eye lens can cost tens of thousands of dollars.