Dallmeyer A.M. 14in 356mm f4 with handmade brass M42 adapter

[Scheimpflug]

Hello! I'm new to both this forum and to large format photography, but I have a new lens and figured this would be the place to learn about it.


I went on a trip last weekend to the nearest city (300km / 4.5h drive), and while there, I was rummaging through a second hand store. Underneath some furniture and an old accordion(!), I discovered a huge lens with a very vintage & homemade looking brass M42 adapter.

http://i741.photobucket.com/albums/xx60/Scheimpflug/Large%20Format%20Lenses/Dallmeyer%2014in%20356mm%20f4/DSC_9736-edited-resized.jpg

The lens has a number of markings on it which, with the help of Google (many of the search results ending up here), have helped me get a rough idea of its origins:
http://i741.photobucket.com/albums/xx60/Scheimpflug/Large%20Format%20Lenses/Dallmeyer%2014in%20356mm%20f4/DSC_9806-edited-resized.jpg
http://i741.photobucket.com/albums/xx60/Scheimpflug/Large%20Format%20Lenses/Dallmeyer%2014in%20356mm%20f4/DSC_9883-edited-resized.jpg
http://i741.photobucket.com/albums/xx60/Scheimpflug/Large%20Format%20Lenses/Dallmeyer%2014in%20356mm%20f4/DSC_9885-edited-resized.jpg

Apparently the J.H.D. stamp and the UU serial number both signify that it is a design/product of the John Henry Dallmeyer company, while the A.M. and the arrow signify that it was built for the UK Air Ministry for use as an aerial photography lens, possibly in the WWII timeframe. Supposedly the "14A" is a design or category, while "3140" is the military contract under which the lens was produced.


The lens itself is quite heavy, and has a large aperture ring that stands out from the lens body. There is a brass block bolted to the ring, perhaps to couple the ring to a cable or some other mechanism? The lens mount threads are ~75mm in diameter, and the filter threads are the same.

The iris diaphragm has 20 blades, which completely disappear when wide open, and become reasonably small when stopped down. Several parts of the front lens ring, aperture ring, and lens body have been painted over and re-etched with different numbers, so I believe this lens started out as a "14in f/5.6", but has now been relabeled to "356mm f/4". The factory aperture markings seemed to have ranged from f/5.6 to f/16, while the hand-engraved numbers range from f/4 to f/11.



I held the lens up to the window with the curtains drawn around it, and by holding a piece of paper up behind it, the infinity focus point seems to be around 80mm behind the M42 flange of the adapter. Since neither the lens nor the adapter have provisions for focusing, my only conclusion is that this was designed to have a bellows or variable extension tube inserted between the adapter and a camera body.

Without the adapter, this lens has a huge image circle. Our estimates with the sheet of paper put it a bit short of two A4 lengths in diameter when focused at infinity... so something like 50cm? I could be wrong, but I think this puts it in "ultra large format" territory?

That's about all I know. Like I said, I'm completely new, so please correct me if anything is incorrect, and let me know if you have any other insight into what this lens was designed for, or what it could be used for.

Thanks!

[Scheimpflug]

Here's a second set of pictures, that couldn't be included with the first post due to the 4 picture limit...

http://i741.photobucket.com/albums/xx60/Scheimpflug/Large%20Format%20Lenses/Dallmeyer%2014in%20356mm%20f4/DSC_9866-edited-resized.jpg

http://i741.photobucket.com/albums/xx60/Scheimpflug/Large%20Format%20Lenses/Dallmeyer%2014in%20356mm%20f4/DSC_9911-edited-resized.jpg

http://i741.photobucket.com/albums/xx60/Scheimpflug/Large%20Format%20Lenses/Dallmeyer%2014in%20356mm%20f4/DSC_9921-edited-resized.jpg

http://i741.photobucket.com/albums/xx60/Scheimpflug/Large%20Format%20Lenses/Dallmeyer%2014in%20356mm%20f4/DSC_9930-edited-resized.jpg

[Pete Watkins]

You've pretty much got it all right. I believe that the 14A means that it's a contract for photographic equipment and 3140 is , as you state, the contract number. WW2 is also correct. Quality has been known to vary.
Have fun with it.
Pete.

[Scheimpflug]

Thanks.

Are there any guides to Dallmeyer serial numbers that would cover this time period to get a more accurate age estimate? The ones I have found only seem to cover up through 1900. (example: http://web.archive.org/web/20061222043249/http://members.aol.com/dcolucci/sn.htm)

Also, does 75mm sound correct as a mount diameter, and does that match any "standard" large format or ultra large format sizes? After seeing the image this lens made on the paper, I'm tempted to pick up a flange and build a camera around it. :cool:

It also seems that the reports of varying quality in these Air Ministry lenses seem to vary by manufacturer.. most of the UU/JHD identified posts that I've found seem to indicate that they found the lenses to be of better quality. But this is just what I've gathered by searching, and I'm probably a bit biased. :)

[Steven Tribe]

This is one of the contract numbers (3140) which isn't listed in VM. They talk about a "no name" Dallmeyer Air Ministry objective at F5.6 and 14" which they think might be a Serrac. I don't think the real coverage will be that large - the F4.5 14" Serrac civilian version covers about 8x10". It is described as a Tessar design - so the coverage would be similar to a IIb Tessar perhaps - which for 14" is also described as 8x10.

[Dan Fromm]

It is an aerial camera lens. The large UK-made aerial cameras of its time shot 9"x9" on 10" roll film. These cameras were not hand-held, were attached to cradles that were attached to the aircraft. Everything bolted together as securely as possible.

Lenses for most aerial cameras -- there are a few exceptions -- were mounted on what are called lens cones. The cone in turn attached to the camera body. The lenses were collimated to the camera -- focused to infinity by moving the lens fore/aft in the cone -- and locked into the cone. That's why there's no provision for focusing. Not directly relevant, but I've had a couple of TTH 12"/4 telephotos for the AGI F-139, a hand-held (sometimes) camera that shot 6x6 on 70 mm film; both showed signs of repeated re-collimation.

I've handled an example of your lens. Tessar, and no doubt about it. I don't know why the aperture scale was re-engraved, this makes no sense unless the diaphragm was reworked to open wider. This may have required no more than removing a stop, but since I've never opened one up I don't know if this is the case.

[Scheimpflug]

Steven-
What is VM, and what is a Serrac? :confused:

Dan-
9"x9" is pretty big, but still seems like only a small percentage (maybe 25%?) of the image produced by this lens. Is there any particular reason why they would have made the lenses so large if they could have reduced the view and made them smaller/lighter?

You wouldn't happen to have any photos of the one you handled, or of the assembled cameras in the aircraft, would you?

I don't know if the diaphragm was reworked on mine or not, but I can say one thing with absolute certainty- there is no way it could open up any further! When set to the hand-engraved "f4", the blades are fully retracted into the side of the lens barrel. Not a single bit of the blades are left exposed in the light path. I do not know if this is normal?

In my two photos above that look through the lens, the first is wide open (f4), and the second is fully stopped down (f11). So those are the two extremes of the aperture adjustment.


Thanks for the replies! :)

[cdholden]

Dan,
I'm curious about the "repeated re-collimation". Do you know if this was due to reusing the lenses through a course of camera changes/upgrades? Or maybe cameras being adjusted to meet focus/calibration spec in the preventive maintenance routine on the aircraft?

Chris

[jb7]

I recently bought a 36" f/6.3, and did some research-

I think this page might be useful-
according to the numbers, it seems your lens might have been matched to an F.52 camera ...


http://www.airrecce.co.uk/cameras/raf_ww2_cameras.html

[Dan Dozer]

I also have a 14" Dallmeyer Serrac. Serrac is the name of this series of lenses that Dallmeyer made. It has all the information on it that makes it appear to be the commercial version, but the F-stop range is only from F4.5 - F11 so I'm assuming that it is the Air Ministry type used for Aerial photography as others have suggested. The lens looks very similar to yours without the huge extension piece that yours has. There is a pretty good chance that your lens is also a Serrac.

Without getting into the complicated terms of glass/lens types, the lens has a lens element on the front and back of the lens, but not in the middle. I believe that this is what a "tessar type" is, but others who know much more about this can respond to that.

The lens that I have has much more coverage than what others may be saying. I've used it for full length portraits on my 8 x 20 camera. Comparing it the a lens like a Voighlander Heliar (on the outside, they look very similar) for example, this lens has an image circle much larger than the 360 MM Heliar. Note that the Heliar has three lens groups not two so it is a much different lens type.

From what the Vada Mecum mentions - there is a little info noted, but not a whole lot. One thing that it does say is "An especial claim was that the rear glass was about the same diameter as the front giving more even illumination and that while flair was kept to a minimum, there was a generous coverage for the use of rising fronts". They are noted as both pre and post war and post war versions might be coated.

I haven't really used my Serrac very much so I can't really say a lot about the performance. I think that this is a lens type that not many people have much experience with. It might be one that photographers with ultra large format cameras (larger than 8 x 10) might be interested in because of the coverage.

Hope this helps.

[Dan Fromm]

Scheimpflug, there are many rules of thumb in photography. The f/4.5 tessar rule of thumb is that the lens covers roughly 110% of its focal length. I have no idea what you mean by coverage -- everyone seems to have his own definition -- and can't see what you see. I can't believe that the lens covers 50" as you suggest. Might you be misreading ", which means inches, as cm?

About the aperture. Try to measure the lens' transmission. I bet it t/stops around t/5.6 wide open. And measure the entrance pupil. I bet it is 2.5" wide open.

I've never laid hands on whatever camera y'r 14"/5.6 was made for. If you're really interested, you might want to buy a copy of Roy Conyers Nesbit's book Eyes of the RAF. It is more about people and operations than about equipment but mentions many cameras, relatively few lenses.

Chris, the AGI F-139 is an electrically driven development of the clockwork Williamson F-134. The AGI Agiflite is a later development still. All use the same mount. The 12"/4 lens screws into its cone where it is held in place by four radial setscrews that are glued in. Getting them out is really pleasant. My evidence of recollimation is scars in the lens' threading left by setscrews. My first 12"/4's mounting screws were so badly scarred that it wouldn't come out of the cone. Steve Grimes set poor Adam Dau to extracting it. I authorized using a hacksaw, instead Adam put lapping compound in through the setscrews' holes and worked it and worked it and worked it for hours. He's still annoyed.

I don't know why the RAF recollimated 'em; my best guess is that not all F-139s had exactly the same flange-to-film distance.

I still have one cone, s/n 032. Jim Galli may still have the other one I bought, s/n 015. 032 has a little plate marked "Modifications" with five spaces. It has had Mod No. 1, 2, and 3.

Cheers,

Dan

[Scheimpflug]

I think this page might be useful-
according to the numbers, it seems your lens might have been matched to an F.52 camera ...

http://www.airrecce.co.uk/cameras/raf_ww2_cameras.html

Thanks, that gives me something else to search for. :cool:



I also have a 14" Dallmeyer Serrac. Serrac is the name of this series of lenses that Dallmeyer made. It has all the information on it that makes it appear to be the commercial version, but the F-stop range is only from F4.5 - F11 so I'm assuming that it is the Air Ministry type used for Aerial photography as others have suggested. The lens looks very similar to yours without the huge extension piece that yours has. There is a pretty good chance that your lens is also a Serrac.

Without getting into the complicated terms of glass/lens types, the lens has a lens element on the front and back of the lens, but not in the middle. I believe that this is what a "tessar type" is, but others who know much more about this can respond to that.

The lens that I have has much more coverage than what others may be saying. I've used it for full length portraits on my 8 x 20 camera. Comparing it the a lens like a Voighlander Heliar (on the outside, they look very similar) for example, this lens has an image circle much larger than the 360 MM Heliar. Note that the Heliar has three lens groups not two so it is a much different lens type.

From what the Vada Mecum mentions - there is a little info noted, but not a whole lot. One thing that it does say is "An especial claim was that the rear glass was about the same diameter as the front giving more even illumination and that while flair was kept to a minimum, there was a generous coverage for the use of rising fronts". They are noted as both pre and post war and post war versions might be coated.

I haven't really used my Serrac very much so I can't really say a lot about the performance. I think that this is a lens type that not many people have much experience with. It might be one that photographers with ultra large format cameras (larger than 8 x 10) might be interested in because of the coverage.

Hope this helps.

Thanks, Dan. Mine does indeed have exactly the same size (diameter) lenses in the front and back, at least in terms of the part that is visible. I don't think mine is coated, and when I look into it from either end under a bright light, I can see 6 strong reflections. Does that match with what is expected for a Tessar?

I would be interested to see a photo of yours, if you have one.



Scheimpflug, there are many rules of thumb in photography. The f/4.5 tessar rule of thumb is that the lens covers roughly 110% of its focal length. I have no idea what you mean by coverage -- everyone seems to have his own definition -- and can't see what you see. I can't believe that the lens covers 50" as you suggest. Might you be misreading ", which means inches, as cm?

About the aperture. Try to measure the lens' transmission. I bet it t/stops around t/5.6 wide open. And measure the entrance pupil. I bet it is 2.5" wide open.

I've never laid hands on whatever camera y'r 14"/5.6 was made for. If you're really interested, you might want to buy a copy of Roy Conyers Nesbit's book Eyes of the RAF. It is more about people and operations than about equipment but mentions many cameras, relatively few lenses.

Chris, the AGI F-139 is an electrically driven development of the clockwork Williamson F-134. The AGI Agiflite is a later development still. All use the same mount. The 12"/4 lens screws into its cone where it is held in place by four radial setscrews that are glued in. Getting them out is really pleasant. My evidence of recollimation is scars in the lens' threading left by setscrews. My first 12"/4's mounting screws were so badly scarred that it wouldn't come out of the cone. Steve Grimes set poor Adam Dau to extracting it. I authorized using a hacksaw, instead Adam put lapping compound in through the setscrews' holes and worked it and worked it and worked it for hours. He's still annoyed.

I don't know why the RAF recollimated 'em; my best guess is that not all F-139s had exactly the same flange-to-film distance.

I still have one cone, s/n 032. Jim Galli may still have the other one I bought, s/n 015. 032 has a little plate marked "Modifications" with five spaces. It has had Mod No. 1, 2, and 3.

Cheers,
Dan

Dan- What I typed in my first post is that the image circle is ~50cm diameter... not sure where you read inches? So, to clarify, holding the lens up with a huge empty canvas behind it, when it is focused at infinity, the circular image projected onto the canvas measures ~50cm in diameter. :) (I actually think it is a bit larger than 50cm... maybe 52 or 53 cm where the vignetting starts? I will need to rig something up to measure it more accurately.)

Doing the math to find the largest square that fits in this circle, I solved for an isosceles right triangle with a hypotenuse of 50cm, ending up with a 35.36x35.36 cm square, just a hair under 14x14". 14x14 = 196 square inches, vs 9x9 = 81 square inches.. So I guess a 9x9 frame would be using more like 40% of the image area, not the 25% I guessed before... but it still seems like an awful lot of extra that could have been designed away to lighten the lens.


How do you measure the transmission of a lens? :confused:

For the entrance pupil, the front lens element is exactly 2.5" wide, and when you look through it, aside from a bit of magnification (and dust :) ), it is as if nothing was there. You can't see the diaphragm at all, you just see straight through to the edges of the rear element.

My lens has perfect threads - no evidence of any setscrews ever being used.



Thanks again for the replies, this is all very helpful information.

[dsphotog]

Cool lens!
I just bought one that looks like it on this very forum!
Mine has a standard mounting flange, No shots yet, I haven't had a chance to make a board for it.
Mine also is marked, 14A/3140, but not A.M. The aperture ring is engraved for F stops 5.6-16
It's ser#UU285965 & marked 14IN F/5.6 & has a Burke & James Inc sticker on the barrel.
Happy shooting!
David Silva
Modesto Ca

[Dan Dozer]

Here are a couple (bad) photos of my Dallmeyer Serrac. You'll notice something a little different about yours and mine. Mine has a little lever out the side that you grab to change the F-stop. Yours has a little projection out the side that I'm assuming was there to attach into the aerial camera for changing the F-stop. Perhaps this means that mine was intended for the commercial market as opposed to aerial photography. Would seem odd that it only stops down to F11. However, other than those to things, I think the two lenses look pretty much the same.

What a Tessar is supposed to do regarding reflections, someone else here on the forum will need to address that. That's beyond my experience level. Sorry, I can't check it just now, I'm out of town on a business trip.

Dan

[Jim Fitzgerald]

Cool lens!
I just bought one that looks like it on this very forum!
Mine has a standard mounting flange, No shots yet, I haven't had a chance to make a board for it.
Mine also is marked, 14A/3140, but not A.M. The aperture ring is engraved for F stops 5.6-16
It's ser#UU285965 & marked 14IN F/5.6 & has a Burke & James Inc sticker on the barrel.
Happy shooting!
David Silva
Modesto Ca

David, let me know how the lens performs so I can then have sellers remorse.

Jim

[dsphotog]

Threads like this one are certain to increase lens mystique/demand/value!
Kinda like Verito & Heliar lenses.

[Scheimpflug]

Cool lens!
I just bought one that looks like it on this very forum!
Mine has a standard mounting flange, No shots yet, I haven't had a chance to make a board for it.
Mine also is marked, 14A/3140, but not A.M. The aperture ring is engraved for F stops 5.6-16
It's ser#UU285965 & marked 14IN F/5.6 & has a Burke & James Inc sticker on the barrel.
Happy shooting!
David Silva
Modesto Ca

Thanks for the reply, David.

Based on what I have read, the "UU" prefix in your serial number would indicate that yours is also a Dallmeyer. I wonder if Burke & James had imported/resold it at some point, or perhaps even sold it mounted to a camera? Aside from the missing "A.M.", does your lens have the large arrow symbol, or perhaps a crown?

With the mounting flange on yours, do you know if these were standardized? In other words, if I wanted to build a large-format camera around my lens, are the lens threads some standard diameter/pitch?

Also, would you be able to take a few pictures of your lens? The most helpful would be a photo of the aperture ring, and two photos looking through the lens with it wide open and fully stopped down. This would help me understand if the internals of my lens actually have been modified, and if so, by how much. :cool:




Here are a couple (bad) photos of my Dallmeyer Serrac. You'll notice something a little different about yours and mine. Mine has a little lever out the side that you grab to change the F-stop. Yours has a little projection out the side that I'm assuming was there to attach into the aerial camera for changing the F-stop. Perhaps this means that mine was intended for the commercial market as opposed to aerial photography. Would seem odd that it only stops down to F11. However, other than those to things, I think the two lenses look pretty much the same.

What a Tessar is supposed to do regarding reflections, someone else here on the forum will need to address that. That's beyond my experience level. Sorry, I can't check it just now, I'm out of town on a business trip.

Dan

Dan - When you get back from your trip, would you be able to take the equivalent photos of your lens (aperture ring, iris diaphragm wide open, and iris diaphragm fully stopped down)? With these three data points, this would let us make a good comparison of the differences between the Air Ministry and civilian versions. :cool:

Also, perhaps it is just me, but the aperture lever on your lens almost looks a little "homemade"? :confused: It looks quite thin & flimsy in comparison to the massive ruggedness of the lens... I also notice that your aperture ring has grooves machined into it, which would seem to indicate that it was intended to be grabbed by the hand... while my Air Ministry lens has a smooth ring, perhaps to save costs because it was coupled via that block and not operated directly? It also looks as though your aperture ring is flat on the top, whereas mine is somewhat "dished"...

[Scheimpflug]

... and two more comparisons:



I found this Dallmeyer 14in/5.6 Anastigmat on ebay, which looks similar to my lens:

http://i.ebayimg.com/23/%21BnguCfQ%21Wk%7E$%28KGrHqIOKjQEtksub,ThBLjv6qLPoQ%7E%7E_12.JPGhttp://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=370308382631

I don't know what its smallest aperture is, but it is quite clear that it stops down significantly more than my lens. This lens has the same "dished" style of aperture ring as mine, but a bit different surround for the front element - a flatter name ring, and thinner metal for the front tube (the part that has the filter threads).



I also came across a forum posting with this Dallmeyer 36 inch f6.3, with the MoD arrow:

http://static.photo.net/attachments/bboard/00U/00UYkC-174933684.jpghttp://photo.net/no-words-forum/00UYUP

This lens is interesting as it has a very similar block bolted to the aperture ring. This gives me a bit more confidence that this block was part of the original installation in the aerial camera, and not added to my lens for some other purpose by the person who constructed the brass adapter.

[jb7]

That's the one I mentioned earlier, the 36".

It's a telephoto, ic of around 20" - 22" at infinity-
(I haven't measured properly yet-)
ff distance is around 50cm at infinity-

It covers 20x24 at around 0.8x magnification, so I'm tempted to try some portraits at some point...

My one doesn't have that tab, or any holes to mount it-
must have been used in a different camera...

[dsphotog]

Mine has the large arrow.
The flange is part of the barrel, it looks just like the ebay one.(except it doesn't say Dallmeyer) It also has a thread about 75mm, or 3 inches. Looking at yours again, it looks like perhaps your flange was machined off,(the bright metal ring on the barrel).
Here's a link to Jim's ad that I bought from, with the picture, (he may be having sellers remorse)
http://www.largeformatphotography.info/forum/showthread.php?t=63149

[Dan Dozer]

Dan - When you get back from your trip, would you be able to take the equivalent photos of your lens (aperture ring, iris diaphragm wide open, and iris diaphragm fully stopped down)? With these three data points, this would let us make a good comparison of the differences between the Air Ministry and civilian versions. :cool:

Also, perhaps it is just me, but the aperture lever on your lens almost looks a little "homemade"? :confused: It looks quite thin & flimsy in comparison to the massive ruggedness of the lens... I also notice that your aperture ring has grooves machined into it, which would seem to indicate that it was intended to be grabbed by the hand... while my Air Ministry lens has a smooth ring, perhaps to save costs because it was coupled via that block and not operated directly? It also looks as though your aperture ring is flat on the top, whereas mine is somewhat "dished"...[/QUOTE]

Let me see what I can do about getting some photos of it. The aperature lever on my lens does look flimsy and in fact it is. I'm sure that it is factory made, but it clearly isn't strong enough for the size of this lens and it has been bent more times than once in it's past history.

[Scheimpflug]

That's the one I mentioned earlier, the 36".

It's a telephoto, ic of around 20" - 22" at infinity-
(I haven't measured properly yet-)
ff distance is around 50cm at infinity-

It covers 20x24 at around 0.8x magnification, so I'm tempted to try some portraits at some point...

My one doesn't have that tab, or any holes to mount it-
must have been used in a different camera...

It may be a bit hard to see when it isn't in your hands, but the tab/block isn't actually bolted through the aperture ring - it just has two parts which clamp on to it from the sides. The two screws are actually outside the ring.

http://i741.photobucket.com/albums/xx60/Scheimpflug/Large%20Format%20Lenses/Dallmeyer%2014in%20356mm%20f4/DSC_9911-edited-resized.jpg

Now that I think about it, I wonder if this block is the reason for the "dished" shape of the ring? If so, it might explain why Dan Dozer's civilian lens has a simpler "flat" ring. Otherwise, I would have expected the civilian version to be "fancier" than the military version.



Mine has the large arrow.
The flange is part of the barrel, it looks just like the ebay one.(except it doesn't say Dallmeyer) It also has a thread about 75mm, or 3 inches. Looking at yours again, it looks like perhaps your flange was machined off,(the bright metal ring on the barrel).
Here's a link to Jim's ad that I bought from, with the picture, (he may be having sellers remorse)
http://www.largeformatphotography.info/forum/showthread.php?t=63149

Interesting! I hadn't known that these had the flange built-in, and I was wondering why mine had the one polished part but everything else painted! :)

So if that is the case, what was the purpose for the rear threads? :confused:

[sun of sand]

The ones that don't stop down all the way can of course be machined out easily
if youre looking to use the lens
you get to f45 before the blades really tighten and tweak
replacing the blades after the mod is easy with the barrel being so large
could probably do the whole job in 25 minutes
mine needed the old grease changed as well with the aperture ring being very sticky

the threads on mine fit but perhaps not perfectly the flange for my 10.75in Celor

[Scheimpflug]

The ones that don't stop down all the way can of course be machined out easily
if youre looking to use the lens
you get to f45 before the blades really tighten and tweak
replacing the blades after the mod is easy with the barrel being so large
could probably do the whole job in 25 minutes
mine needed the old grease changed as well with the aperture ring being very sticky

the threads on mine fit but perhaps not perfectly the flange for my 10.75in Celor

Thanks for the tip! Do you have any suggestions or how-to guides for disassembling these lenses? Would I be best to start at the front or the back?

Even if I wasn't going to modify it, it would be interesting to open it up anyway, just to see if it has been modified in the past. :)

[Steven Tribe]

They were all made during wartime and Dallmeyer and others sub-contracted the manufacture to other establishmnets. If there is no Dallmeyer, JHD or VV - then someone else made it. The 36" is commonly termed "Big Bertha" and has trouble with colour correction. There were many surplus to requirements after 1945 - so were a special offer up to around 1950. They were typically adapted to be used for sport's photography - Cricket in the UK and New Zealand.

[Scheimpflug]

If there is no Dallmeyer, JHD or VV - then someone else made it.

"UU" as well. :)



They were typically adapted to be used for sport's photography - Cricket in the UK and New Zealand.

Hadn't heard that before! Do you have any more information about this usage? Was it amateur photographers / hobbyists who did this, or professionals? Do you know how they were typically adapted, or what camera formats were used?

Thanks. :cool:

[Steven Tribe]

Once again, Vade Mecum has a write-up! Production of the AM 14a wartime lenses was at a high level due to expanding no. of aircraft and plane losses! The market "collapsed" in 1945 and the unused and undamaged lenses were on offer up to around 1950. I think the UK producers were very unhappy about the further sale which reduced the demand for "new" lenses. I think the sports modification were generally professional whilst the bird watchers version was more likely to be home-made.

I seem to remember that UU (also on Dallmeyer designs) was an abreviation for manufacture at National Optical - a wartime assembly plant set up by T,T & H.

[sun of sand]

Thanks for the tip! Do you have any suggestions or how-to guides for disassembling these lenses? Would I be best to start at the front or the back?

Even if I wasn't going to modify it, it would be interesting to open it up anyway, just to see if it has been modified in the past. :)

the front element group on mine was tough to unxscrew -as they've been on others- but I eventually got it using a thick rubberband for extra grip
The elements all screw into place so it's an easy take apart/put together
just do it

My lens had a moderate amount of haze which cleared up completely


I don't have that thicker aperture handle thingy, though. I don't think that would complicate anything

I've never installed aperture blades before so I'm glad this lens was my first
very easy to do

if you want to modify it get a dremel/cutting disk
it doesn't change anything cosmetically
youll just be able to close down to f45

[Dan Dozer]

Sorry, it's taken a while for me to get photos of my Dallmeyer Serrac. Hope these show a little more on what the "user" lens has that may be different from the AM lens.

First two photos show lens at wide open at F4.5 and closed down at F11. Note that when I originally got the lens, the iris was stuck. I took it apart and fixed it and noted that if I wanted to enlarge the groove to allow the iris to close down more, it wouldn't have been difficult.

Third photo shows the apperature ring. It's somewhat hard to read because mine isn't as cosmetically nice looking as yours (it seems to have had a much harder life). Noted F-stops are F 4.5, 6, 8, and 11.

Fourth photo shows the lever that is screwed to the aperature ring that you can use to open/close the iris. It appears to be factory made, however, it clearly wasn't made strong enough as it has been bent a few times in it's past life.

I'm real curious that if this lens was intended for the general public rather than aerial cameras, why would they only make it to go down to F11?

[Richard Kaye]

I just got a very similar item from ebay. Mine is an AM 14" lens. Front and rear cells are both about 65mm in diameter. Total weight about 1.2kg. Rear cell unscrews easily and is obviously a doublet (no air space). Front cell is an air spaced pair, so I conclude it's tessar-style. Mine has the same A.M. code and a UU number, and is also stamped JHD10 so I am pretty sure its Dallmeyer. It's uncoated and in great condition. F stops 5.6,8,11 and 16 only.

I just discovered that it mounts on my sinar really really easily. The hole size required is exactly the size of the hole in a "top hat" panel when the central extension is removed, and the real element protrudes through the board just enough to get close to but not foul the old sinar copal shutter I have. (And the 65mm diameter is perfect for this too with no vignetting.) So I am happy - even if it is not the greatest lens in the world it will give me a new "look" to play with. Testing this weekend.