Information sought on a lens by C Burr, London

[Andrew Plume]

Hi Paul

I believe that you're on:-

http://britishphotohistory.ning.com/...sg_mes_network

any joy for you on there................??

regards

Andrew

[pgk]

Yes. Tying specific photos to being taken on specific lenses during the 1850/60s is not easy, but I have certainly found a few, or have discovered specific photographers/locations/dates which I am now trying to find the photos from. Some photographers left a great 'evidence trail' but others did not. It also appears that equipment and its attributes has been a cause of controversy and discussion from the start of photography!

[peter brooks]

Could you tell me the physical dimensions of your lend please?

My lens has a hood, and a black band just below it but they look similar. Nice to see that the 'L' of London is in an identical script

(Metric inches seems so wrong but that is digital verniers for you).

The barrel is 2.25" diameter approx (slightly under).
Back of the flange to start of the hood (top of black band) is 2.9".
Back of the flange to the Waterhouse slot is just over 1.25"
Rear glass is just under 2", front glass looks to be the same.
Flange threads are about 2.5".

The rear group unthreads, the front doesn't (and I don't see a reason to try to persuade it right now).

With the rear group removed I get four reflections from the front group, and three from the rear. Does that mean an air spaced double at the front and a cemented double at the rear? I don't know enough about lenses to decode this to a 'type' but would be interested to know.

The focal length looks to be just over 15", gg to slot.

[pgk]

Looks fairly similar but they are not identical - mine is 2" in diameter and never had a hood (no provision for one). I get 2 reflections from the front and 2 from the rear. I wonder if Mr Burr was a one man band, building to orders?