Panoramas from a fisheye

I’ve been trying out generating proper panoramas from pictures taken with a Sigma 8mm fisheye lens lately, and I’m quite pleased with the results. This example is taken from a group of six shots I took while in Ronda in southern Spain; I stitched them together using Hugin, asked Hugin to convert the output to equirectangular format, and ran it through the (trial version of) Pano2VR. Much to my surprise the output’s really pretty decent; the original images look somewhat squished, but the actual output quality’s really pretty reasonable.

A single fisheye shot actually produces not a bad result on its own; this example is another shot taken in Ronda but with just a single image imported into Hugin. However, I found that if you’re stitching at all, you need to use at least three or four shots or Hugin will not have enough information to figure out the appropriate orientation for the second shot. That causes you to end up with a really messed up stitched output. If you know for sure that your horizons are straight, you can probably get around that by restricting it so that it can’t change the image roll, but I can’t see it being a reliable way to get decent output.

Below are some of the source images for anyone who’s curious.