Hi all,

So a professor at my university has retired, and opened up his lab for others in the faculty to take useful equipment. Today, I went and I picked up some equipment, but this lens caught my eye. It was a big, heavy and beautiful optic. So naturally, I took it with me. The others in the lab don't know what it is, and I thought the people here might know something about it.

http://www.flickr.com/photos/34593726@N05/3641870235/
http://www.flickr.com/photos/34593726@N05/3641870247/

It was made by Aldis Brothers, Birmingham UK. Stamped on the wooden box was "No. 14A/3418" and " 20" f6.3 ". Those two markings are also on the lens as well. The only other distingushing marking on the lens is "EE 189284", as you can see in the photo. Sixteen blade aperture, twist adjustable from 6.3 to 32. No mechanical shutter. No electronic connects. Weighs about 8 pounds. 6 inches wide, 7 inches tall.

We _think_ it may have to do with military aircraft, as there was also some other optics from the WWII and Cold war era planes. There were also some eyepieces from the Palomar Observatory in California, so we might be completely off the mark. Also some film/slide projectors were floating around. So we were thinking somewhere around 1940-1980. Wish I could narrow that down.

I'm certain it was used as a photographic lens, but what photography was this used for? What kind of camera used this beast of an optic? Where? When? Etc...

Anyway, I was just curious and thought people here might know something about it. Full sized photos available upon request.

Cheers,

I would think "20" must be 20cm = 200mm. Couldn't say anything else about it...

You could get some idea of the size of the image circle and measure within a few millimeters, the backfocus or lens register to film distance by holding the lens up horizontal with a piece of white paper or cardboard and focusing the image by changing the distance between the 2. A horizon scene would be a good infinity target to use.

If the backfocus appears to be greater than 45mm or so, stick a Canon or other digital body up to it and try to take a picture.

Looks like an old view camera lens from a wooden view camera. Many of them were shutterless as those long exposures were done by removing the lens cap. I'm guessing very early 20th century.

Tested the thing out a bit more. It's a 20inch = 500mm focal length lens, and the image circle is at least 6x6 inches. I'm stuck with bad lighting, so that's with the sunset through a window.

Fascinating stuff, I didn't look too hard but found this scan from one of their brochures. They certainly weren't cheap


http://www.gracesguide.co.uk/wiki/Aldis_Brothers

Tsopauly wrote:
It was made by Aldis Brothers, Birmingham UK. Stamped on the wooden box was "No. 14A/3418" and " 20" f6.3 ". Those two markings are also on the lens as well. The only other distingushing marking on the lens is "EE 189284", as you can see in the photo. Sixteen blade aperture, twist adjustable from 6.3 to 32. No mechanical shutter. No electronic connects. Weighs about 8 pounds. 6 inches wide, 7 inches tall.

We _think_ it may have to do with military aircraft, as there was also some other optics from the WWII and Cold war era planes. There were also some eyepieces from the Palomar Observatory in California, so we might be completely off the mark. Also some film/slide projectors were floating around. So we were thinking somewhere around 1940-1980. Wish I could narrow that down.

Looks like a WW2 era lens, perhaps from a photo reconnaissance setup, like you've guessed. Any gun sights in the collection? I've posted a question on this item on the WW2 aviation forum that I host, hopefully that will generate some interesting information.

Ruy

from Lens Vade Mecum 3ed ( http://www.antiquecameras.net/lensvm.html ):

"In an Aldis case, a 20in f6.3 5-glass lens has been noted from WW2 and has an EE serial prefix to the number. Thus there may be two aero series."

Well, after a weekend of searching, I've exhausted the easy to get to information resources that's available to me.

Here's what I know:

Daytime battlefield, high altitude (40,000+ feet), Aerial reconnaissance lens.
20 inch focal length, f6.3
Film used: 9" x 9" or 10" roll (or for us metric people: 18 x 24cm)

A (crown) M means UK Air Ministry
Reference Numbers 14a/#### denote aerial photography equipment.
EE-###### is 'vintage Air Ministry code' for 'Aldis made it'.

Usually mounted on an F52 Camera, on Spitfires and Mosquitoes and post WWII, on Canberras.

Designed by John Henry Dallmeyer (1830-1883) and Thomas Ross (1859-1906) at 19 Bloomsbury Street, London. Made by Aldis Brothers Limited in Birmingham UK. Still can't find the year of manufacture, because they were in business until the late 1940's.

Wow, I feel like I'm on the Antiques Roadshow....

References:

-Airplane Photography, H.E. Ives. J.B. Lippincott Co, London, 1920. Page 61.

-Encyclopedia of Nineteenth-Century Photography, J. Hannavy (ed.). Routledge, 2007. Page 376.

- Handbook of Photography. McGraw-Hill, York Pennsyvania. 1939.
Ross Xpress Lens Diagram on page 46.

- Mosquito Photo-Reconnaissance Units of World War 2, M W. Bowman. Osprey Publishing (1999)

========================

Ronan,

I actually have the same lens that's on that advertisement! Mind you, it's the military standard one though! 8inch, f2.9 Astigmat. (Dallmeyer Pentac (AM 14A/780))

Ruy,

Yes, there were also gun sights and rifle sights too.

Tsopauly wrote:
Ruy,

Yes, there were also gun sights and rifle sights too.

Thanks for the updated info.

Wish I had been there to take a look at the aircraft gun sights (reflector, gyroscopic?).

Ruy

Tsopauly wrote:
Well, after a weekend of searching, I've exhausted the easy to get to information resources that's available to me.

Here's what I know:

Daytime battlefield, high altitude (40,000+ feet), Aerial reconnaissance lens.

Must have decent sharpness...

Pretty amazing that the same lens was used on Canberras, which makes it even early cold war (into 60-ies) equipment.

Ruy