Fishy Fun with the GIMP
I signed up with 23HQ so I could share photos with the good folks at for critique & help.

When I acquired a fish-eye lens, a number of the good folks offered help. Monoceros and Kevin were very helpful
in helping me to understand the value of wide-angle shots. They gave me some good advice, which was very much
like the advice given here:

[Hint for EdKiefer: both Bob Atkins and Ken Rockwell offer good set-up guides for most cameras]

I especially like this quote: "Ultrawide lenses are the most difficult lenses to use well." Fish-eyes are ultrawide.

So I was very happy that Rolf did an episode on fish-eyes, it's nice to see how other people approach them.

Along the way I have come to appreciate the community here at 23HQ as well, and find ideas & inspiration here.

I have a long background in information technology, meaning I like software where I can examine the actual code,
which is why I use Open-Source software for processing my images. Having never used much of anything else, I
do not know whether or not it is better than proprietary software. But many people seem to think there are a
number of very good tools in the Open-Source world. GreyCStoration (noise removal) and its successor G'Mic
are very possibly the best of the bunch - some would even say better than Noise Ninja (don't know / can't say).

I have gathered a number of excellent GIMP plug-ins & scripts long the way, which I used to process this very
interesting (and very 'green') picture by Rolf. Most of my favourite GIMP tools were written by Ray Adagio
(follow the links at and my workflow here used his 'CA correction with Hugin' and also
'straighten & crop' plug-ins (fish-eyes show lots of CA, and who doesn't need to rotate a picture occasionally?).

After that I used the colour curve I extracted (with a great script by elsamuko) from Rolf's XCF (GIMP-format)
project file, followed by Noise Reduction (first version), and finally sharpening. The picture seemed fairly sharp
(composing with a fish-eye is tricky, normal procedure seems to be to tape the aperture and focal distance, and
then compose solely by looking at the edges. They don't seem to have a focal plane as such [although they have
lots of Chromatic Aberration]. You are never entirely sure what the final picture will look like until you see it).

However, I decided the noisy version looked better and that over-sharpening (so amplifying the noise) just gave
the picture more atmosphere. So the noisy version is sharpened more strongly than the Noise-Reduced version.

You can seem more of Rolf's pictures here:

(2 photos in total)

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