A. M. lens: Who made it? "W W" code = ???

[Carsten Wolff]

I recently acquired a cheap and cheerful, but actually pretty nice 5" f4.5 Anastigmat.
It is an "A.M." lens i.e. made for the British Military.
There is no maker on it; just a code "W W" and then the serial number.
Vademecum says UU, or VV are Dallmeyer...what's WW though?

Any help appreciated, thanks.....

[IanG]

Ross handled the contracts, they were the major contractor for the Air Ministry and took over the Carl Zeiss factory which was set up a couple of years before WWI, mainly to produce Binoculars but some camera lenses were made there as well.

Ross sub-contracted some production to Dallmeyer etc.

You might compare your lens to the 5" Ross Anastigmats, see if it's similar.

Ian

[Dan Fromm]

Carsten, what is the lens' serial number? I ask because the Air Ministry lenses I've paid attention to all had serial numbers that fitted the maker's s/n sequence. No help with N.O.Co, alas.

[Carsten Wolff]

Dan, the number is 29717.

[IanG]

One problem is that prior to WWI Ross were manufacturing a wide range of Zeiss and Goerz lenses under licence. Prior to the war they were marked as such, during the war they went unmarked, no royalties were being paid.

My Ross AM lens, a 151mm f16 wide angle, is an unmarked Protar, just says Ross 151mm and the serial number. Ross seem to have been less keen for sub contractors to add their own names.

A photo might help. there are adverts around for all the major UK lens manufacturers of that period.

Ian

[Dan Fromm]

Carsten, that s/n is out of range for the major makers. NOCo, perhaps, but as usual I could be mistaken.

[Carsten Wolff]

Here's a pic:
http://www.flickr.com/photos/37082363@N08/5494164470/
Thanks for your help, guys.

[Andrew Plume]

Carsten

there's no link.....................

andrew

[Carsten Wolff]

That was weird: When I edit the post, the link is there; when I look a the post , it's gone....Sorry, here it is again:
http://www.flickr.com/photos/37082363@N08/5494164470/
The pic is of the website I bought it of.

[Dan Fromm]

Carsten, it looks much like the 5"/4.5 Ross WA Xpres I used to have. I convinced myself that mine was made by Ross, its s/n was VV xxxxxx

[Carsten Wolff]

Thanks, Dan and others!

[tuant]

For the Dagors, does A.M still mean British Air Ministry? I have a Dagor in that version. Since A.M products were made for the Air Force, doesn't it mean that the products are of better quality than those none A.M. versions? Thanks!

Tuant

[IanG]

Dagors marked Goerz Am Opt or similar mean they were made by Goerz American Optical which was by then an independent company owned by CP Goerz sons in the US.

Ironically the US forces were using Goerz Am Opt lenses etc in WWI while the Germans were using similar made by CP Goerz, Berlin.

Ian

[Sevo]

For the Dagors, does A.M still mean British Air Ministry? I have a Dagor in that version. Since A.M products were made for the Air Force, doesn't it mean that the products are of better quality than those none A.M. versions? Thanks!


As has been pointed out, there have been other meanings of "Am", especially concerning Goerz.

Air Ministry labelled lenses were made for the British Air Ministry in WWII (the Air Ministry was not established until after WWI), under special laws that allowed them to pool the British optical industry. Essentially all production facilities could be requested to make any design, regardless of patents and competitor status.

A.M lenses (and indeed all aerial lenses made by all parties in WWII) were of worse quality than the corresponding peace-time versions - thanks to materials shortages, an increase in production well beyond the numbers they had an experienced workforce for, and the relatively low longevity requirements for items installed on planes which were statistically expected to be shot down within weeks or months.

[IanG]

The Air Ministry was formed during WWI in 1917, although the necessary act of Parliament went into force at the beginning of January 1918. So some AM lenses are very much earlier than WWII.

Ian

[tuant]

As has been pointed out, there have been other meanings of "Am", especially concerning Goerz.


A.M lenses (and indeed all aerial lenses made by all parties in WWII) were of worse quality than the corresponding peace-time versions - thanks to materials shortages, an increase in production well beyond the numbers they had an experienced workforce for, and the relatively low longevity requirements for items installed on planes which were statistically expected to be shot down within weeks or months.

Thanks, guys! That means I should avoid AM lenses in the future:-)

[Dan Fromm]

Thanks, guys! That means I should avoid AM lenses in the future:-)I don't see why.

The RAF didn't stop buying aerial cameras and lenses to fit them when WW-II ended. I have a couple of post-war TTH A.M. lenses that are outstanding. 4"/2.0 Anastigmat (2 1/4" x 2 1/4") and 12"/4 Telephoto. The 4" covers 2x3 wide open and is better from f/4.5 down than the highly regarded 101/4.5 Ektar. Bigger and heavier, though. The VM says the 12" just covers 4x5. It is the longest lens that's comfortable on a 2x3 Speed Graphic but doesn't put image at the ends of the frame because of vignetting by the bellows.

Other air forces bought aerial cameras and lenses for them too. USAF, for one. Many, not all, of the lenses that the USAF flew are very good and some (far from all) of them can be adapted to modern cameras.

That said, I'd be leery of cruddy old brand-X 8"/2.9 Pentacs.

In my opinion, which is not based on much good data, when a lens, e.g., the 38/4.5 Biogon, was sold to an aerial camera manufacturer such as AGI and to civilians all buyers got the same quality. AGI may, however, have had more stringent acceptance tests than, say, Hasselblad or Alpa. Same goes for the Zeiss lenses supplied for Agiflites; these were also mounted in for Hasselblad and Rollei.

That said, some of the lenses that armed forces bought were definitely second best. On this point, look up what Leicanuts have had to say about M-mount lenses made to military specifications.

There's some evidence that Soviet lens makers, purveyors to east-bloc air forces, had as much difficulty with quality control as they did with lenses made for civilians. I have only one Soviet aerial camera lens, a 100/2.5 Uran-27. Its ok; if I had to use it instead of the 4"/2.0 TTH I wouldn't feel sorry for myself but it isn't up to the TTH.

[Carsten Wolff]

I just pretty much confirmed that it is indeed a Ross Express Wide Angle. The same lens was often fitted to 6x18cm Vought-Solar Aircraft Torpedo cameras (San Diego) in the '40s. Thanks again.

[Ian Greenhalgh]

I have two of these lenses, f4.5 5". They are a 4/4 double gauss design. One of mine has the WW code and the s/n 27473, the other has no code but the s/n 26705.

They are not Ross Wide Angle Xpres, I have two of those as well, and those are a 6/4 plasmat with much larger glass.

Both the Ross WA Xpres and this mystery 4.5/5" were fitted to the Vought-Solar torpedo training camera.

Here is an example of the 4.5/5" fitted to said camera:

http://www.flickr.com/photos/heritagefutures/5463175083/in/set-72157626099002858

Here you can see a Ross WA Xpress 4/5" on the left and a mystery 4.5/5" on the right:

http://www.largeformatphotography.info/forum/attachment.php?attachmentid=93653&d=1366438756

http://www.largeformatphotography.info/forum/attachment.php?attachmentid=93655&d=1366438762

I've just managed to cram the cells from one of the 4.5/5" into a spare Alphax #3 I had to hand so I'll try it out on 5x7 shortly.

[Pete Watkins]

NO.Co = National Optical Company. As far as I've managed to find out this outfit was set up in Leicester (the same Leicester where the TT&H factory is)in the early part of the WW2 to produce lenses for the military. A lot of the staff were from TT&H. I have no idea when production started or finished.
Pete.

[Andrew Plume]

as far as I'm concerned, 'WW' is Ross

and Ian, what you've shown earlier today are imo two lenses both made by Ross, they're completely different than those made by Dallmeyer and TTH, I haven't I admit waded back through this post

.....and Pete is of course, spot on

andrew

[Ian Greenhalgh]

Andrew, what makes you think it's made by Ross?

The two lenses are completely different, they both have heavy brass barrels but the design of the barrels has little in common.

I have no idea who made the f4.5/5", it doesn't fit into any of the product lines of any of the makers as far as I can tell. Dallmeyer's version of the 4/4 double gauss was an f6.5 and the closest they made to 5" was 5.25", TT&H's version was an f6.5 too. Wray made a double gauss for aerial use, an f5.6/6".

The closest I can find would be the unsymmetrial f4.5 version of the Ross Homocentric introduced in 1912, and this f4.5/5" is indeed unsymmetrical.

[Andrew Plume]

Ian, thanks

it's the 'sheer design' only, they're way way closer to Ross lenses than the other UK manufacturers. There are plenty of people in the UK who would straight away say that that's 'a Ross lens'

also I go straight to the shape of the barrel and cut out any reference to the likes of 'double gauss' - another indication, to me, for determining which manufacturer is the f stops

information regarding the AM badged lenses per se, is, I understand, not always available and some of it, as has been indicated is open to some doubt, certainly the AM lenses weren't as good quality. as say a 'pukka Dallmeyer lens' - from memory, Steven Tribe has said this on here too

regards

andrew

[Andrew Plume]

anyhow, does it really, really matter who manufactured your lenses?, enjoy them instead.........let us know how they stack up on image quality, post some images too, they always help

regards

andrew

[Ian Greenhalgh]

To be honest, the barrel has almost nothing to do with the origins, I have Dallmeyer lenses with very similar brass barrels.

I'm not going to fall into the trap of making a generalisation not based on facts such as 'AM lenses were of lesser quality', I'll judge each lens based on it's own abilities.

There is absolutely no difference in the quality of the barrels of these AM lenses and 'pukka' lenses of the 1930s, the material is heavy, quality brass, the machining is of the same standard, it's quite surprising considering the need for brass for munitions.

I have several other AM lenses, most notably a Pullin London Pulnar f2.8/4" which was used for a target recognition system that projected silhouettes. I use it as a taking lens on my Century Graphic 2x3 and it is fabulous, sharper than my Schneider Xenar 3.5/105, my Ross Xpres 3.8/105, my Voigtlander Skopar 3.5/105, my Kodak Anastigmat Special 4.5/105, so it is a very fine lens indeed.

So I'm not subscribing to the AM lenses are of lesser quality theory, like any theory it needs to be supported by strong evidence and I haven't found any so far apart from the pot metal my Pentac 2.9/8" is made out of having corroded, but that is hardly unusual for an aluminium alloy of pre-1950s construction and you will find many alloy lens barrels that were nothing to do with the AM with similar corrosion.

[Dan Fromm]

Pot metal is a zinc, not an aluminum (aluminium in Commonwealth countries), alloy.

Ian, the VM mentions an f/4.5 5" WA Xpres. f/4.5 is very fast for a 4/4 double Gauss type wide angle lens. I take it that you decided the lens is a 4/4 double Gauss after counting reflections. Do look again. I make this suggestion because the dim reflection from the glass-cement-glass interface can be very hard to see.

For evidence of this, look at an RF-2,-3,-4 or -5 process lens (FSU lenses). The 1963 GOI catalog says they're 6/4 double Gauss types. Until given this hint neither Arne Croell, who is very discerning, nor I, who isn't always, could see the dim reflection from the inner group. Up to then both of us thought these lenses were dialytes.

[Ian Greenhalgh]

I thought 'pot metal' just referred to alloy of uncertain composition that had been produced by melting down old cooking pots?

Yes, 4.5 is suspiciously fast for a double gauss. I'll see if i can open the rear cell and see if it's a cemented doublet or two airspaced elements. Given that this lens covers 6x17, that seems rather large coverage for a tessar type.

I have a few lenses that I can't figure out the design from the reflections, a S.O.L. 4.5/184mm for instance, it seems to be quite complex as there are a ton of reflections, not been ale to open it and find out for sure. Same with the Pullin London Pulnar 2.8/100, the VM suggests a tessar type, but the reflections don't appear to match other tessars, I'm probably just crap at counting reflectons. :)

[Andrew Plume]

To be honest, the barrel has almost nothing to do with the origins, I have Dallmeyer lenses with very similar brass barrels.

I'm not going to fall into the trap of making a generalisation not based on facts such as 'AM lenses were of lesser quality', I'll judge each lens based on it's own abilities.

There is absolutely no difference in the quality of the barrels of these AM lenses and 'pukka' lenses of the 1930s, the material is heavy, quality brass, the machining is of the same standard, it's quite surprising considering the need for brass for munitions.

I have several other AM lenses, most notably a Pullin London Pulnar f2.8/4" which was used for a target recognition system that projected silhouettes. I use it as a taking lens on my Century Graphic 2x3 and it is fabulous, sharper than my Schneider Xenar 3.5/105, my Ross Xpres 3.8/105, my Voigtlander Skopar 3.5/105, my Kodak Anastigmat Special 4.5/105, so it is a very fine lens indeed.

So I'm not subscribing to the AM lenses are of lesser quality theory, like any theory it needs to be supported by strong evidence and I haven't found any so far apart from the pot metal my Pentac 2.9/8" is made out of having corroded, but that is hardly unusual for an aluminium alloy of pre-1950s construction and you will find many alloy lens barrels that were nothing to do with the AM with similar corrosion.

thanks Ian

I'll take your word for it Guv, it means very little to me, you have your view, I have mine, it's part of what this Forum is all about

anyhow, what's all this stuff about "falling into a trap", I haven't set one

regards

andrew

[Dan Fromm]

Re pot metal, see http://en.wikipedia.org/wiki/Pot_metal

[Pete Watkins]

Just to lighten this whole subject up a bit. I recently tested a "UU" 14" lens on 4x5 and I can't see how we even won the bloody war. I'm keeping it for soft focus though, it'll never be sharp.
Pete.

[Dan Fromm]

Just to lighten this whole subject up a bit. I recently tested a "UU" 14" lens on 4x5 and I can't see how we even won the bloody war. I'm keeping it for soft focus though, it'll never be sharp.
Pete.

Pete, thinking of weight, the one of those monstrosities that I've picked up and looked at and set down again was so filthy inside and out that I doubted it would clean up at all. How cruddy is yours?

[Pete Watkins]

Dan, it came apart nicely and there's very little crap there. I't's probably what used to be known as a Friday afternoon lens (they'd all been to the pub at lunchtime and just wanted to get home for the weekend). Stuff flew through QC in the afternoon just to clear the benches for Monday morning.
A lot of people who owned Rover cars in the 60's & 70's knew about this syndrome, not to mention Lucas............Oh God, not Lucas!!!
Pete.

[Dan Fromm]

Rover. You would mention Rover. I had a P6B. Do not ever mention Rover to me again.

[Steven Tribe]

certainly the AM lenses weren't as good quality. as say a 'pukka Dallmeyer lens' - from memory, Steven Tribe has said this on here too

No - not me. I have never even owned an AM 14a etc.
But I have contributed with some background (secondhand info) about the use of temporary production sites after 1940, by Ross, Dallmeyer, T,T & H and NOS. So makeshift production facilities as well as a temporary workforce, probably did have an effect on both quality of production and quality control. But many AM lenses where either made pre-1940 and in the better period, post 1943. Many AM lenses never got to be used and were disposed of in the late 40's and early 50's to an eager public as not much else was available.

I always thought that "Monday morning" cars were even worse, due to missing and hungover staff. The UK didn't make reliable cars after the separate chassis system was given up. I was another sufferer in the 60's and early 70's.

[Ian Greenhalgh]

I don't have much time for internet nonsense to be honest, if you listened to every 'fact' you heard on the internet, you'd never learn much of value.

So I prefer to ask the lens what it can do.

Here's my 4.5/5" in it's new home in an Alphax #3. It's one of those restricted aperture Alphaxes from an oscilloscope camera and used to house one of those 1.9/3" Oscillo-Raptars. The maximum aperture opening just happens to be the same as the diameter of the glass of this lens so they make a perfect fit together. I'll be using this lens/shutter on 5x7 and I'll report how it does.

107255

[Andrew Plume]

........err, sorry Steven

v best

andrew

[Andrew Plume]

exactly Ian, exactly

.........look forward to hearing what it can do etc etc

what's this about "......internet nonsense...."???

andrew

[IanG]

I don't have much time for internet nonsense to be honest, if you listened to every 'fact' you heard on the internet, you'd never learn much of value.

So I prefer to ask the lens what it can do.

Here's my 4.5/5" in it's new home in an Alphax #3. It's one of those restricted aperture Alphaxes from an oscilloscope camera and used to house one of those 1.9/3" Oscillo-Raptars. The maximum aperture opening just happens to be the same as the diameter of the glass of this lens so they make a perfect fit together. I'll be using this lens/shutter on 5x7 and I'll report how it does.

107255

So what's the aperture restriction on the shutter ? The main problem with that particular WA AM lens is it only stops down to f11 in it's normal barrel I see a few of them every year and always for more than I'd pay for them.

I have a 180mm f4.5 CZJ Tessar with a similar restricted aperture range in a strange US shutter with a single speed, it looks like it was possibly a pre-WWII US military lens with a mechanical linkage to adjust the aperture.

AM lenses go back well before WWII as Steven Tribe says, I have an Ross AM 141mm f16 WA that covers 10x8 and is obviously a Ross Protar.

Ian

[Ian Greenhalgh]

I was lucky, I bought two of these 4.5/5" together in a job lot of junk for next to nothing. The apertures in both didn't work, but the glass was fine. Yup, like the more common Ross WA Xpres 4/5" they only close to f11 in the original barrel.

The restriction in the Alphax shutter is simply that the blades don't open as far as they do in a normal Alphax, apparently you can open them and remove a pin that causes the restriction.

I haven't recalculated the aperture yet, but I think it will close to f64 now, if not, f45, so it has a much more useful range in this shutter than it did in barrel.

[Ian Greenhalgh]

I forgot to mention, I opened the rear cell and it has two airspaced elements, so it's not a tessar type.

I can't get the front open, but the external curves are different to the rear cell so it's asymmetrical.

I've drawn the layout as best as I can determine, in the hopes that someone might be able to identify what it is:

107256

[Dan Fromm]

The UK didn't make reliable cars after the separate chassis system was given up. I was another sufferer in the 60's and early 70's.

Abandon that idea. The Rover P6 was a unit-body car. And my Scimitar coupes were body on frame, also reasonably reliable.

Ian, MoD bought 14"/5.6 Aviars as well as 14"/5.6 tessar types.