I've been thinking about getting a fisheye lens for use with a K20D; usability with film would be nice but not essential.
The leading candidate is the Pentax 10mm-17mm/3.5-4.5 fisheye zoom, but other options appear to be:
Zenitar 16mm/2.8
Peleng 8mm/3.5
and the harder to find
Sigma 16mm/2.8, 8mm/3.5 and 8mm/4
Pentax 16/2.8.
Two questions:
-- To Zenitar/Sigma/Pentax 16 owners: do you use your lens much at f/2.8-3.5 (i.e. is there a useful advantage over the 10-17 zoom for available-light work)?
-- To those familiar with the zoom and at least one prime: Do any of the primes have an advantage in resolution, contrast, or flare/ghosting resistance over the zoom?
I haven't found any hard data comparing the zoom with any of the primes (or the primes with each other) so I'd like to hear your opinions.
Because you need shorter focal lengths on a DSLR for any given field of view, conventional fisheyes for film coverage just look like badly barrel distorted wide angles on the DSLR format.
If you want the fisheye look, the 10-17 Pentax lens is probably your best bet, wih the Peleng perhaps a choice as well.
On Nikon, the Peleng is best used with mirror lock, as it can damage the mirror (it extends back far enough to catch the mirror). Is this an issue with Pentax?
The manual isn't much help. http://www.k3camera.com/k3/k3pdfs/8mmlens.pdf
-- To Zenitar/Sigma/Pentax 16 owners: do you use your lens much at f/2.8-3.5 (i.e. is there a useful advantage over the 10-17 zoom for available-light work)?
-- To those familiar with the zoom and at least one prime: Do any of the primes have an advantage in resolution, contrast, or flare/ghosting resistance over the zoom?
I find my Zenitar has a moderate soft-focus effect at f/2.8. I think image quality is better on the zenitar (less objectionable CA), but I use the 10-17 a lot more since it's much wider. The autofocus and aperture control on the Pentax are nice to have too.
Just got the Sigma 15mm f2.8 and yes, I do use it at f2.8.
It makes a perfect lens for inside photography, and even at f2.8 it is sharp and has enough depth of field to be usable.
I have the Sigma A/2.8 15mm and use it outdoors at night with black and white film. It seems fairly sharp wide open except at the VERY edges with good depth of field. I love shooting crowded scenes at night with this and the speed definitely makes a difference.
I used to have a Rikenon fisheye in the 90's (I believe it was a re-badged Pentax) which broke, and I have missed it since.
Last year I got the DA10-17 fisheye, and I love it. I had some boring but important use for it in my profession, but I soon found many more interesting ways to use it. For a while perhaps too much (the kids were asking after last x-mas why the x-mas-three was tilting in the pictures, but really it is an excellent tool when trying to fit all relatives, the x-mas tree and dining table in one picture). It's good for street shooting and people, good with some sort of "macro". Purple fringing is there in some situations, but I can't say it have disturbed me. It must be impossible to make such a lens and make it fulfill normal criteria for what is quality in a lens, so I tend to forgive it for its weakness thanks to its other good sides. I have not felt the max aperture as a limitation, as it works so well now with the K20D to turn up the ISO. You are not going to play around with razor thin DOFs anyway on such a lens.
Though I am looking for some extreme wide angle or fish eye with an aperture ring for my LX I haven't owned a fish eye prime at the same time as the DA10-17 and hence not been able to compare them so I can't really help you with your actual questions. But I can say this that I suspect that it is the best you can get for a digital camera with a 1.5 crop factor. If you buy a fish-eye made for a film SLR you don't really get a fish eye, but a bad wide angle on your DSLR.
"Macro" with the DA10-17. Is this what I would see if I was a bee and came in flying right after my sister-bee?