Fisheye lens, which one

[David Cockey]

There are multiple lower cost fisheye lenses available from brands including Samyang/Rokinon, Laowa Venus Optical, TTArtisan, 7artisans, Meike and AstrHori. Differences include field of view and stated focal length. I understand there are also differences in the details of the fisheye projection. 

What have been experiences using fisheye lenses with Metashape? Which lens? What size sensor (full frame, crop, MFT, etc)? How well did photo alignment work?

[tazzo]

I have good results with a Sigma 16mm, wider lenses have more issues because of distortion

[David Cockey]

I am specifically interested in fisheye lenses, not rectilinear wide angle lenses.  I have experience the equivalent of 16mm wide angle lens. Use will be inside the ends of boat hulls.

[tazzo]

Maybe you can simulate someway the lens with a 3d software and reconstruct with metashape syntethic images to have a better ideas of the system performance.