Cheap fish eye lens?

I want to have some fun with a fish eye lens on the k1 but I don't want to spend more than 100 pound on it. Does such a thing exist ?

Saw one on Amazon closest to your budget. No idea if full frame though.

link

I paid exactly £100 on Ebay for the SMC Pentax-F Zoom Lens 17-28mm F3.5-4.5 Fish-Eye. It's FF, auto focus, small, and does the job - hours of fun guaranteed!

For a review of this lens see this set of user reviews and some samples. The problem is that only the first review is for the lens on Full Frame, all other reviews are with APS-C bodies. Nevertheless, the pictures with the first review give a good impression.

Being produced from 1995 to 2004 it's old - designed for film, but if you see one it's worth looking into.

I'm sure others will be able to advise on prime lenses by other brands, but as far as I know, they are all manual focus.

I have an old Sigma 15mm f2.8 EX 180 degree full-field fish eye, AF lens acquired 2nd hand back in 2007 for around £100 which I have found to be a lot of fun on my recently purchased K-1. I was also surprised to find it recognised in LR5 which attempts to correct its natural distortion which I think is probably better turned off.

It might be worth having a look to see if you could find one of these.

Glyn

Try one of these:
http://www.ebay.co.uk/itm/ASTRON-SUPER-WIDER-SEMI-FISH-EYE-LENS-58MM-SER-VII/132...
Budget fish-adapter which screws in front of a standard lens. I've had one for ages. Oddly it is possible to see the lettering around the edge of the adapter so I painted over it.
There is Youtube video, albeit a poor one IMHO (due to poor taste and presentation of unnecessary distorted 'music') that shows it in use:
https://www.youtube.com/watch?v=zeiFBGV5zWI
It's a cheap way to find if a real fish-eye lens is right for you.

As for a real fish-eye there's the Samyang 12mm
http://www.northlight-images.co.uk/samyang-12mm-fisheye-lens-review/
It's pretty sharp at the edges and in the corners.

hey thank you a lot for the advices

Zenitar 17mm f/2.8 is a FF fisheye lens.

I was going to buy the 16mm but then I thought the 16mm is maybe not wide enough?

It's pretty wide!

I use the 10-17 in crop mode on my camera. It covers the FF circle after 15mm or so but the corners aren't the best. Crop mode is adequate as I don't really need all the resolution.

With fisheye lenses the usual relationship between focal length and field of view breaks down a bit. The improtant thing is to know whethr or not a lens is full frame (not in the format sense) or just a circle in the middle of the frame. Then, the field of view should be around 180 degrees. A few fisheyes can be 160 degrees and one is even 220 degrees (not Pentax).

The fisheye front converter is a cheap place to start just to see how it goes. It isn't the best quality though. The 10-17mm on an APS-C body is a fantastic lens. The 17-28mm is the full frame version, if you can find one. I see it's back in the lens roadmap, so hopefully eventually it will appear.

thanks a lot, what do you think about the Zenitar 16mm? I look at the photos and they are not too bad.

Zenitar 16mm might be a bit basic in its manufacture, but the glass could be good.

Only F17-28 :0
It is ultra small have AF and is wider than Laowa 12mm