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timing
8-Jan-2011, 07:51
So, over Christmas whilst back in the UK, I was 'persuaded' to go around an antique centre. Whilst mulching around I came across a brass lens marked as Magic Lantern. One look showed that whilst a bit dusty it seemed to be in very good condition and at 20 decided to buy it.

Opening it up there are 2 uncemented elements at the rearand a cemented pair at the front. No makers markings at all. Except, a couple of places on the lens housings and the base of the ratchet there is VIII scratched / engraved into the brass.

So, with such little information any punts on id'ing the lens or lens type?

Tim


Here's a few pictures to help:

goamules
8-Jan-2011, 08:15
It's a petzval design. The seller's description of "Magic Lantern" is the only ID you can be sure of.

Steven Tribe
8-Jan-2011, 10:25
You can see the front thread where there was a heavy front section (about 1.5cm wide) with a "clap" and a wide slot for glass filters. Or a brass lens hood - if it was a pre-Waterhouse stop portrait lens ( 1% chance, perhaps)! There are quite a few small casting faults in the brass which points to an early product.

Pete Watkins
8-Jan-2011, 11:14
As it's a silver colour according to information I've seen on this forum in the recent past we should assume that it's nickel plated and that this process was not invented until the 1880's.
Pete.

timing
8-Jan-2011, 15:21
Interesting comments guys, thanks. I should add that the front thread is for a hood which I have but didn't include in the photo. I also have the brass cap for the hood.

I did wonder given the viii marking if this was a lens that was made for 'rebranding' and engraving with another brand post manufacture. Is this possible?

Steven Tribe
8-Jan-2011, 15:38
These roman figures follow a tradition in assembly to make sure that parts that actually fit and matched. In the days of hand cut threads, there was no certainty that everything that was supposed to fit did fit. I have telescopes from 1780 and 1810 that have similarly rough roman numerals - so it is an old tradition.
Post photos of the hood and cap. This is getting quite interesting.

timing
9-Jan-2011, 01:49
Here's a photo of the lens with hood and cap. Also, a photo of the plate that holds the rachet in place - now the number 8 there maybe purely co-incidental but it's not scratched into the brass, it's engraved.

timing
9-Jan-2011, 01:50
As the silver colour, I think that's a white balance effect. The lens is deffo brass with no coating.

Steven Tribe
9-Jan-2011, 02:37
I really don't know about this one! I didn't think it was nickel plated.
There are magic lantern objectives that look almost the same as the early "anon" photographic Petzvals (pre 1860's). Did the glass have a slight greenish tint or completely without colour? The "8" has been stamped, but even small workshops had hand stamping tools.

timing
9-Jan-2011, 02:47
Hi Steven,

the glass has almost no colour at all.