this post was submitted on 01 Feb 2025
75 points (100.0% liked)

What is this thing?

6371 readers
198 users here now

Let us help you identify that mysterious object you’ve found.

Currently in CHALLENGE mode: If you've got something obscure knocking about, post a picture, and let's see how we do. Please prefix such posts with "CHALLENGE:" so we know we've got a fighting chance.

founded 2 years ago
MODERATORS
 

1000016939

It has 4 lenses in total, two at each end. The only text on it is the number 50, stamped into the bottom of the ring that goes around the outside to attach it to whatever it goes with

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 16 points 1 month ago* (last edited 1 month ago) (2 children)

Camera or projector lens, probably of petzval type.

Edit: the lack of an iris or slot for waterhouse stops makes me think projector lens.

[–] [email protected] 20 points 1 month ago* (last edited 1 month ago)

My first thought, too. Its almost identical to the image from wikipedia's article on petzval lenses, even.

[–] [email protected] 6 points 1 month ago

If you look at the photo of a magic lantern here https://blog.scienceandmediamuseum.org.uk/christmas-magic-lantern-slides/

The front lens cap is very similar.