My thinking is it's a Petzval that someone tried to clean and put it back together out of order.
Kent in SD
maybe it is a reversed tessar because light travels through the lens
Originally Posted by Raphael
opposite with a camera than when projected ?
looks like a fun objectif
I'd vote for it being a modified Petzval. As this page from the 1890 Ben. French Catalogue (found here, thanks to Dan Colucci) clearly states, photographers have pernicious habits of taking lenses apart and screwing them up! There were many variations on the design tried by lens-makers during the 19th century. http://www.antiquecameras.net/petzvallens.html has extensive material if you're interested.
Originally Posted by jnanian
Your question is an interesting one, and maybe any optics pundits around can answer it ?
As the Tessar is not a symmetrical design, should it be reversed if the lens is used as a projection lens ? Logicaly I would think the answer is yes, but is this sure ?
@Whiteymorange, thanks for your reply.
I discovered recently the antiquecamera.net website, it's a goldmine !
The design of my lens looks like a little the Dallmeyer portrait lens, as described on the petzvallens page. However i am inclining too for a mistakenly remounted Petzval. The fact that this lens was very clean for its age when I found it is aiming me this way.
A check procedure will be to mount it on a camera and see what I get on the groundglass, but I haven't the appropriate lens board for now.