Originally posted by obsolescence Fisheye distortion can be corrected to yield an even wider angle of view than any rectilinear lens. I wonder how edge sharpness compares?
I did a test of this once. . . With the gear that I had available at the time, the results came out very similar. I was surprised by that, but it seemed like digital correction and optical correction (with lens elements to make it rectilinear) did the same things to the image, and with the same shortcomings. The practical difference is that the rectilinear lens was huge and heavy! The fisheye gave me a small, lightweight, inexpensive lens that could perform double-duty, since I could choose to de-fish or not. But of course, I didn't get to see a rectilinear view when composing and shooting. I just had to imagine how it would come out if I de-fished it.
As for "an even wider angle of view than any rectilinear lens". . . Do you know that Voigtlander now make a 10mm rectilinear lens for Sony E-mount? Yes, with full frame coverage. Seems like black magic to me.