Quote Originally Posted by Fotoguy20d View Post
What's the construction? Is it a petzval? If the front is a cemented pair, it'll make a nice meniscus lens with FL about twice the lens, and lots of coverage (and funky effects). I have a set of photos on flickr from a lantern lens minus the rear elements. Before you do anything else, try reassembling the two halves into the frame and shooting through it. You can also paint the broken edges with a sharpie (which is easily removed)./ATTACH]
It's probably a petzval (cemented pair at the front, then one larger element, a small spacing and a third thin element at the rear. It looks similar to the Dallmeyer design - but is unnamed)
Using it as a meniscus would be a bit problematic, the focal length would be close to 30", which is way too long for anything I have planned.