Anyone know what this is?

[gooseholla]

You mean my lens comes off something that small?!

John

[Astrobits]

Can you determine it's focal length and therefore it's F/ratio?

Might help to determine it's function.

Nigel

[rowan46]

I think you are all wrong,  its obviously some sort of futuristic thing sent back in time look at  the year of manufacture 2938  possibly some sort of temporal probe

[JamesF]

By chance I've just noticed this on AB&S: http://www.astrobuysell.com/uk/propview.php?view=96717

James

[0030]

Thought it would be some kind of nautical lantern. Nope JB80 called it. it’s a petzval lens.

http://en.wikipedia.org/wiki/Petzval_lens

There is one similar listed on ebay for $12,500

http://www.ebay.com/itm/RARE-EARLY-Brass-Voigtlander-Sohn-in-Wien-Petzval-Lens-c-1846-1847-S-2761-/361260775059?pt=LH_DefaultDomain_0&hash=item541cd1f693

Concept art for some one who is actually building such a camera.

http://www.gizmag.com/35-foot-camera-vanishing-cultures/21178/pictures