To fish-eye, de-fish or wide-angle?

Kunstmuseum Stuttgart
The New Art Museum, Stuttgart

After calibrating my Samyang 8mm Fisheye, I went downtown Stuttgart to try it out for the first time. I thought, the new Art Museum would be a great subject: a lot of straight lines, very lean and clear design. I was keen to find out, how the 8mm Fisheye would compare to a normal 8mm wide-angle lens, so I took the Sigma 8-16mm zoom with me, as well. The idea was, to take a few pictures from the very same position and later on de-fish the Samyang pictures and compare them to the wide-angle shots.

The de-fishing can be achieved in Lightroom by using lens profiles. Since there is no lens-profile for the Samyang in Lightroom (at least, not for RAW photos, I could not find any in the Adobe Lens Profile downloader), I was forced to experiment with the lens profiles, Lightroom offers. The following pictures all were de-fished using the Sigma DG 15mm f/2.8 EX lens profile. I think, it matches quite well, but not perfectly. For my purposes, it was sufficient, though, when applying some extra lens barrel correction and vertical transformation (when needed).

First of all, I was eager to find out, how the de-fishing would alter the picture’s perception. It’s really interesting, what dynamics the de-fished pictures have. The steps for example extend quite more to the background, the perspective gets quite dramatic. The horizontal viewing angle in the center stays the same, the de-fishing of course will let you loose quite some of the almost 180° viewing angle in the upper and lower parts of the picture. The vertical viewing angle will be limited, as well. Just compare the attached photos, and you can judge for yourselves. But there’s one caveat, which I was to find out about quite soon: this only applies to pictures taken in portrait mode…

Then next experiment I wanted to conduct was to de-fish a picture and compare it to a 8mm wide-angle shot from the very same position.  I  noticed the same dramatic effect with the “depth” of the picture, when de-fishing it. But then I was surprised, that the horizontal viewing angle wasn’t as wide as I had seen it with the above pictures. The explanation lies at hand with a bit of thinking: viewing angles of the Samyang 8mm Fisheye are not 180° in all directions. Using it in landscape mode, you will get almost 180° vertically, but not horizontally – the portrait mode is the opposite. Also, I was not very happy with the de-fishing in terms of perfectly straight lines. The lens-profile I was using (remember: there’s no Samyang profile, that I know of) produce quite some crooked lines. You can easily see that in the big horizontal steal beam in the upper part. Also, you will note quite some blur in the outer parts of the picture – this is caused by the quite big distortion necessary to achieve the de-fishing.

So, now let’s finish with the comparison of the Sigma 8mm wide-angle lens. Horizontal and vertical viewing angles are even more limited, and the perceived depth of the image is much smaller. This is not to criticize, though – this is just how this lens works. I think, it’s like “comparing apples and pears”, as we say in Germany…

All in all, I must say, this was an interesting experiment. I learned quite a bit about how lenses will alter the perception of a subject, how a fisheye lens can be used to achieve dramatic effects and what downsides de-fishing can but must not have. I’d be interested, what your experiences are – so just drop a comment down below!