180+ degree field of view?

[duckarrowtypes]

This question is going to require a little bit of "off label" thinking, I think.

I have an 8x10" camera and I would like to know what my options are for getting a lens that can see a 180 degree field of view. I don't WANT this lens to cover the entire 8x10 frame so the image circle should be somewhere between, say, 4 and 8 inches in diameter.

What's out there?

edit: I should say that I really don't need a shutter either as my exposures are in the 30+ second range.

edit 2: this is the kind of image that I'm after: uncorrected fisheye (http://upload.wikimedia.org/wikipedia/commons/b/b4/Fisheye_photo.jpg).

[Jim Galli]

pinhole is about it. Even the amazingly expensive Hypergon quits at 140 degrees.

[John Schneider]

Do some research on "Pleon" and "sky lens." Maybe you can cobble something together from surplus optics that would approximate a LF version of this design, which does cover 180 deg.

[Glenn Thoreson]

Edmund Optics has some interesting lenses. Maybe discussing your needs with them would turn up something. My 65mm 4X5 pinhole doesn't even come close to that effect. Cool image! :D

[lenser]

Check the auction site for Spiratone and look into one of their old add on fish eye lenses (usually go for around $30-$50. They were made to fit over the "normal" 50mm lenses for 35mm work, but also worked for any lens you could attach them to including large format. (I've used mine on both Hasselblad and 4x5 gear.)

Spiratone offered many different mount rings for whatever you would use this on, but you will possibly have to have a machinist make one for whatever lens you prefer to use.

With a "normal" focal length lens (for which ever format you shoot), you will get a full circle fisheye effect. With longer than normal lenses, there will be a crop so you get more of a curvilinear effect with a full frame film coverage.

Because your lenses have different maximum f stop openings, there is a system built in that lets you set the lens focal length and then calculate the effective f opening while stopping down for your choice of stops.

Spiratone sold this with an instruction sheet. Maybe you can find one of those as well. However, it's pretty easy to figure out the system.

Not absolutely tack sharp, but surprisingly good quality.

Good luck.

Tim

[lenser]

#300231469249

This one is on ebay right now if you're in a hurry. I just Googled "Spiratone fisheye" and discovered that what looks like the exact same auxiliary lens was branded by several different companies including Samigon, Soligor and others, so you might just search for "fisheye lens" or "auxiliary fisheye" on ebay and see what comes up.

[W K Longcor]

That Spiratone fisheye is a real winner if you are after that 180 degree view. I used mine quite a bit on the 4x5 ( never tried 8x10 with it) with very good results. Several times it saved the day when I needed a really wide lens -- I would crop a square or rectangle out of the image and had corner to corner 180 degree - without the circle effect. I've made 16x20 prints from these photos that were very acceptable. Not bad for a "cheap" lens!