Dallmeyer archive “R” interpretation in the serial number lists

[mhayashi]

I always enjoy and look up Dallmeyer serial numbers in Dallmeyer Archive.

Yesterday I was looking up a serial number of 3C and noticed the same serial number appeared twice in the same page, for example 27313 here.

http://thedallmeyerarchive.com/Records/Volumes/lensbook3/Portrait%20Settings/Extra%20Quick%20Acting%20Settings/3C.pdf

The second show in the list is noted “R” above the serial number.
I first guessed the serial number sample was “Rebuilt from” or “Replaced for” the serial sample above the next row.

But chronologically it doesn’t make sence.

The second guess I thought up is “Resale as used to” or “Restock” in the same row.
The third guess is “Repaired for”.
The fourth guess is “Rent to”.

It seems that “R” appears quite a few times.
“R” rows tend to be listed close to the first production date.

They also tend to have the received date to Dallmeyer factory close to or same as the shipping date to a final customer or an agent.

The receivers of the second show of the serial number tagged “R” tend to be different from the ones of the first production.

I have to look through other “R” samples to narrow in the tendencies in other original lists remained.

Another hint is for example here in the 2B lists.
In p58, there are three consecutive rows with “R” above

24889
26154
26155

All came in May 21st, then all were resold? to the same person or agent named Spencer, a different buyer from the original one, but these three samples were all bought by the same person/agent called Mouekhoden? at different times.


Added Aug.14th, 2024, I stumbled upon the name Monckhoven while I was looking up different topics, which I remember in sounds similar to the original post here. The person in the archive is probably Désiré Charles Emanuel van Monckhoven (1834–1882). For example, the serial number 26154, was bought at Feb. 28th, 1877 when he was 42 or 43 year old.

Désiré Charles Emanuel van Monckhoven (1834–1882)

His purchase and study might be reflected on his book, Traité général de photographie published in 1880.
https://www.google.co.jp/books/edition/Traité_général_de_photographie/KgMzAQAAMAAJ?hl=en&gbpv=0


p55, p58
http://thedallmeyerarchive.com/Records/Volumes/lensbook3/Portrait%20Settings/Patent%20Portrait%20Settings/B/2B.pdf

p60
http://thedallmeyerarchive.com/Records/Volumes/lensbook2/Portrait%20Settings/Patent%20Portrait%20Settings/B/2B.pdf

Other hints are the same serial numbers appear 3 times, the first appearance always doesn’t have “R”, the second and thirs shows have “R”.
These examples may support the forth guess “Rent to”.

24083
http://thedallmeyerarchive.com/Records/Volumes/lensbook2/Portrait%20Settings/Patent%20Portrait%20Settings/B/2B.pdf

22532
http://thedallmeyerarchive.com/Records/Volumes/lensbook2/Portrait%20Settings/Patent%20Portrait%20Settings/A/2A.pdf

23003
http://thedallmeyerarchive.com/Records/Volumes/lensbook2/Portrait%20Settings/Patent%20Portrait%20Settings/D/5D.pdf

But what happened “R” serial number samples at the end?
May be the final borrowed user bought it?

Another find is 22123 double lined noted “Repair ready?”, which may eliminates “R”’s possibility of “Repaired for”.
http://thedallmeyerarchive.com/Records/Volumes/lensbook2/Portrait%20Settings/Patent%20Portrait%20Settings/A/3A.pdf

This is a kind of the detective work and joyful…

What do you think about the interpretation of “R”?

Another interesting find in the past was 4A was converted to 4B, cutting the barrel length, replacing some parts as in 25426.

http://thedallmeyerarchive.com/Records/Volumes/lensbook2/Portrait%20Settings/Patent%20Portrait%20Settings/B/4B.pdf
http://thedallmeyerarchive.com/Records/Volumes/lensbook2/Portrait%20Settings/Patent%20Portrait%20Settings/A/4A.pdf

[Euphus]

Interesting take on the 'R' interpretation. All of it makes sense. Have you contacted the Brett Archive to get their take on it?

[mhayashi]

No, I wonder if there is anyone who actually answers my questions seriously unless s/he is interested in photography like a curator of a photography museum….

Just for two cents, I summarized the rarity of selected Dallmeyer petzvals….
229193

[Steven Tribe]

My guess would be Returned, but I’ll look through the items you discovered to see if there could be another answer “in plain sight”!

It is miracle that the records ended at an accessible site. There is no expertise there, though.

[mhayashi]

Thanks for chiming in Steven…. Looking forward to hearing your opinion.
Meanwhile I have got this far for Voigtlander petzval transitions….
I update pdfs when I find new info regularly with the date on the filename.
I sent an email with my findings to Corrado D’Agostini and he will answer my questions during his summer vacation as he tells me it takes very long time for research….
It wasn’t clear for me about his descriptions about Voigtlander petzval
transitions in his 19th centry German lens book.
Very interesting to learn….

https://www.largeformatphotography.info/forum/showthread.php?166538-Voigtlander-B-serial-transition-to-Portrait-Objectiv-serial-engraving-amp-Nomenclature&p=1645764&viewfull=1#post1645764

[pgk]

It is miracle that the records ended at an accessible site. There is no expertise there, though.

I have been trying to kook up information on lens 20089 which has been stated as being a 6" Portrait lens but keep getting directed to blank pages. Is this normal or am I missing something?

[mhayashi]

Many links are unfortunately dead.
You can still approximate the production year and month by looking up the modern index link.
Then check other lens serial ranges of the start and end date that are close to yours.
That narrows in your sample production year and month.
The assumption is the serial numbering is ordinal and chronological.
Is your petzval 1B for ef 6” or 2B for bf 6”?

http://thedallmeyerarchive.com/Records/Volumes/stockbook4/Indexes,%20lens%20lists/Lens%20list%205-4.pdf
http://thedallmeyerarchive.com/Records/Volumes/stockbook2/Indexes,%20lens%20lists/lens%20list%205-2.pdf

[pgk]

Looks like ~1872 but the lens I'm trying to find information on is this one: https://collection.maas.museum/object/231103 as I simply want to know its specification! (I've emailed the museum too). I suspect that the 6" actually refers to the diameter.

[mhayashi]

Well, you are right.
Check the whs picture and the scale.
The whs diameter is approximately 15cm, roughly 6”.
This implies 6A.

https://collection.maas.museum/object/231103#&gid=1&pid=2

For astrographic photography, scientists used fast long petzvals for taking pics.

The link you posted says:

Portrait lens and accessories, 6 inch, brass / glass / wood / leather, J H Dallmeyer, London, England, 1880-1890, used at Sydney Observatory, New South Wales,
But 20086 wasn’t made in that period, which is contradictory and the curator mistook the lens production date determination, or the engraving was not 20086, maybe 30086??

Unfortunately 6A link is dead again, but you can say the lens was made in between 1
2/8/1867 and 5/2/1875 for No.13171-24210, and the closest number is

Rectilinear Settings (Wide Angle)
No.1
20136
14/6/1872

That gives you a ballpark.

[pgk]

Great. Thanks. I think that the Dallmeyer was an older lens which they already owned - a replacement lens from Howard Grubb was ordered in 1887 and finally arrived in 1890. I'm trying to find out about that one too!

[mhayashi]

Well, I found 20086 is not 6A, but Wide Angle Rectilinear Settings Iaa.

http://thedallmeyerarchive.com/Records/Volumes/stockbook4/Rectilinear%20Settings/Rectilinear%20Wide%20Angle/1aa.pdf

This and the period spec 1880’s indicates the 6A’s serial number is not 20086.

I don’t know much about Grubb lenses but if you have bought the 19th century GB and Irish lens book from Corrado, you may find some info. I also have one but not in my hand at a moment….

[pgk]

Thanks. Well, for a variety of reasons it looks as though the Grubb replacement may well have been 'bespoke' then! As I am discovering, many museum's have rather 'loose' descriptions of their items. Some have stuff so well stored that it is near impossible to extract them for examination too. I have drawn a blank at two museums in the UK where lenses are in off-site storage facilities and few staff seem able to access them.

[MarkWelsh]

Can I point out what an incredible thing it is to be able to ask this question? Very few manufacturers of this period (or indeed later periods) have left us with material like this. That it is so gracefully presented, and preserved, is miracle enough – but to be freely accessible online as well . . .

For anyone interested in the story – because parts of it won't otherwise be told – between 2008-2011, Seán MacKenna digitised the 1863-1902 lens and stock books, along with the other material presented in The Dallmeyer Archive, with permission from The Brent Archive. He was still processing and summarising it when he died in 2012. Since his death, some like-minded souls aimed to preserve the material and released it to the internet in 2014. Since then, it has winked in and out of existence, and now has a number of dead links and missing pages, but remains a beautiful resource.

Seán offered the outline of a Dallmeyer timeline (for instance: serials 45000-55000 derive from 1890-1895), but until recently there hasn't been a serviceable serial number guide apart from MacKenna's estimates, combined with the somewhat sketchy offerings of Les Chiffres Cles and Vade Mecum.

With access to the Brent Archive, and rather a lot of time spent re-appraising and correcting MacKenna's summaries, I've been able to build a more solid and specific timeline for Dallmeyer serials from 1860 to 1983. I'm also working on repairing gaps in the 2014 site. Work on it is drawing to completion within a month or two, but I hope the newly published guide at Delta Lenses will be of service to anyone interested in Dallmeyer's history. More to come . . .

https://deltalenses.com/the-dallmeyer-story/

To a previously raised question: the helpful people currently staffing The Brent Archive are nonetheless complete strangers to the Dallmeyer collection, which was bequeathed to them in 1980 and seems rarely to have been disturbed from its air-condition slumber in the vaults.

[Mark J]

If it's of interest, I can lay my hands on a Dallmeyer design issue record book that starts from the mid-1920's . A lot of these entries will be for industrial optics of one sort or another. It came from Willesden and via a good friend of mine who is now retired.

[mhayashi]

Thanks Mark for your wonderful work!
I am looking forward to seeing the dead links of Dallmeyer Archives.
There are many interesting descriptions in these lists, not just lists of samples, but histories behind the lenses.

Examples are as in this thread “R interpretation.”

and here as in my thread,
https://www.largeformatphotography.info/forum/showthread.php?176796-A-history-behind-the-Dallmeyer-Archive-records-of-lenses-sent-to-%93Philadelphia-%94

Let me know when you finish your work!!
Many respects from Tokyo!

and here is for the specific sample No. 25426, the 4B.
https://fotohandeldelfshaven.nl/product/dallmeyer-4b/
——-
Dear Thom,

I have seen your 4B sample which know the previous owner.

I have a 4B sample already so I don’t need another but I tell you the story.

At the time with the previous owner, I looked up the history of this sample and we talked about it.

This sample has the interesting history.

According to Dallmeyer archive,

The lens was originally made as 4A f4 in Oct. 10th, 1876.

Later it was converted to 4B in July 10th, 1877.

The conversion must required some inner barrel cut to shorten the length, and also the replacement of the rear lens group possibly, the front achromat being the same possibly.

The outer sleeve was changed completely to engrave 4B, keeping the original serial number the same.

Later In sometime 1906-1927, the sample was engraved by the Agent and sold as used.

Kings Rd
26 & 28 Kings Rd., Sloane Sq. City Sale & Exchange 1906 - c. 1927

http://www.earlyphotography.co.uk/site/address_listl.html
https://www.gracesguide.co.uk/City_Sale_and_Exchange


This sample was originally made as 4A on October 10th in 1876, then later on 7/10/1877 converted to 4B by cutting the barrel a bit to adjust the focal length from 450mm to 430mm. Dallmeyer might have changed the lens elements as necessary but both 4A and 4B have the same barrel size and lens element diameters, but the other specs such as lens curvatures, thickness and refractive indices may be different certainly so Dallmeyer might changed the elements but used the same barrel so there might be a sign of the remainder that indicates modifications from 4A somewhere on your sample.

Now here is the conclusion.

The sign of the remainder of 4A is the f4 engraved on the internal barrel!!!

So this 4B is still f3.8, although engraved as f4, as long as the internal iris diameter remains the same for both 4A and 4B.

Very interesting!!

Best,
Masayoshi

[MarkWelsh]

Definitely: I've made a list of all the problem resources - quite a few are corrupt or missing. If necessary I'll rescan them. I won't be able to include them in the Dallmeyer Archive, but I can probably publish the data on Delta.

If anyone currently managing The Dallmeyer Archive wants to get in touch with me, we might discuss how to combine the information into one freely accessible resource. I'm happy to continue the work Seán started.

[MarkWelsh]

If it's of interest, I can lay my hands on a Dallmeyer design issue record book that starts from the mid-1920's . A lot of these entries will be for industrial optics of one sort or another. It came from Willesden and via a good friend of mine who is now retired.

Brilliant - thanks. PM sent.

[mhayashi]

Mark,

Ivan Rose might help you to access to the Dallmeyer Archive.
Do you know him?
He is also on this forum with the same handle name.

[Mark J]

Hi Mhayashi & Mark
I have sent an email to John to ask if he still has the book.
Don't get too excited.. !
First ... I am not doing any work on this. I only use modern lenses, but am happy to loan out the book for someone to scan it ( if we have it ).
Second - this is not as detailed a record of individual lenses as the links you post above. The book is just a chronological handwritten list of design types and their numbers, as the designs were finished .
Third - it goes from about 1925 onwards - so it won't cover the 19th-century lenses that many collectors are interested in. However, it will give info about when lenses such as the Super Six and many cine lenses were first designed.
Fourth ... there is no info about the lenses, eg. how many elements they consist of.

[pgk]

Mark, depending on its size (pages), I may well be happy to scan/photograph it .....

[MarkWelsh]

I've now digitised more than 2,500 pages of material from Dallmeyer's immaculately kept records - almost all of it post-1902. I don't yet have the same permission granted to Sean MacKenna to make it public, but it would make sense to dovetail Sean's work and mine as far as possible. Therefore:

1. Can whoever currently maintains the Dallmeyer Archive website get in touch with me? There are significant gaps in the existing archive that look more like bad links than missing files - if you can't fix them, I can help.

2. If anyone with good knowledge of Dallmeyer's history would like to help prepare and identify some scanned documents, I could use a hand and would be able to share some new material confidentially with them.

[mhayashi]

Mark, I emailed to Ivan about your work.
Let’s see.

[Mark J]

I do hope that I can help you. I emailed my friend John again.

[Mark J]

Good news, John still has the book.
It'll take me a couple of weeks to get hold of it.

[mhayashi]

Good news, John still has the book.
It'll take me a couple of weeks to get hold of it.
That’s wonderful!

[Mark J]

I had hopes to see him this weekend but he took off to Aldborough in Suffolk for the weekend.
I said 'Peter Pears would be honoured'.

[MarkWelsh]

Don't worry - I got the reference! One might have expected a larger overlap of Dallmeyer collectors and early 20th century British music enthusiasts.

[Mark J]

John is an interesting man. He worked for Kodak in the late 70's , in Harrow. Then he moved to Dallmeyer in Willesden. That morphed into Avimo Optical Imaging eventually and shifted to Prestatyn in N.Wales. He was always interested and active in music. I briefly worked at Prestatyn in 2000/2001 and John was my boss, and head of design/engineering. When I started at Avimo, Jon Maxwell ( ex. Dallmeyer, Imperial and Cooke Optics ) emailed me to say "Welcome to Dallmeyer " !
John has been a church organist for many years. He recently re-built a 'free to collect' church pipe organ from Chepstow into his own house. His son Tom is (or was) principal oboeist with the Philharmonia of London.

[mhayashi]

I have added another possible find in the original post, which I posted there.
excerpt

Added Aug.14th, 2024, I stumbled upon the name Monckhoven while I was looking up different topics, which I remember in sounds similar to the original post here. The person in the archive is probably Désiré Charles Emanuel van Monckhoven (1834–1882). For example, the serial number 26154, was bought at Feb. 28th, 1877 when he was 42 or 43 year old.

Désiré Charles Emanuel van Monckhoven (1834–1882)

[Mark J]

I caught up with John at the weekend , and now have these items.
The yellow folder contains a bunch of 1970's and 1980's datasheets/sales info which includes probably the last versions of the Dalmac, Pentac, Serrac, Super-Six, Rareac, etc.
The glass ticket register book is handwritten ( good luck with some of that ! ) and just has line entries for when each design was completed, not necessarily when a lens was first made in production.
Let me know who ( Mark ? ) wants this/these, I can post.

252357

[pgk]

Let me know who ( Mark ? ) wants this/these, I can post.]

How many pages Mark. I can copy them and produce pdfs but it depends on how much there is because it could take some time. I would also need to know where the files would need to go.

[Mark J]

Thanks Paul.
Looking back at my inbox, it looks like Mark could digitise it and was keen to loan the book.
I'll wait for him to give me his details.
I should however send you those British Journal photographic almanacs from 1903 and 1912, you would get a kick out of those !

[MarkWelsh]

How many pages Mark. I can copy them and produce pdfs but it depends on how much there is because it could take some time. I would also need to know where the files would need to go.

If you're happy to do that, I could use some assistance - I have thousands of captures of material from the archive that need to be turned into colour-corrected PDFs. PM me if interested . . . thanks.
It looks like I'm going to be busy digitising the brochures on the way to me . . .
Two weeks ago I was able to digitise a really nice copy of a Dallmeyer lens brochure I was able to date to 1957, though it was advertised as '1940's'. At the moment I'm not able to publish my Dallmeyer archive online, but I don't mind sending information to people privately if it's useful. Working on permission for a full public release, too.

[Mark J]

Mark, thanks for the PM. Reading this comment, I'm wondering if it makes more sense to send the book to Paul ?
Also, is it just the glass ticket register book you are interested in ?

[MarkWelsh]

I'm happy to digitise all the content and (privately) make it available to anyone who wants it – the brochures are equally useful.

Things get lost. I'm concerned about preservation and distribution, so would prefer to receive them first-hand if possible - and to give them kid-glove treatment. But of course it's in your possession and you're free to do what you think best with it. I'm content to end up with a digitised copy of any material that might be another piece of the jigsaw.

That said, one repository of information is our best chance of revealing the full picture - and it can't properly be a forum thread: there are still copyright concerns over publishing this information: when the Dallmeyer Archive was assigned the material, they were also assigned ownership of the copyright. They specifically granted licence to publish the early part of the Dallmeyer Archive in the public domain, but such permission has not - yet - been granted for the newer material. Therefore public online placement of this material isn't strictly allowed and public online placement of old brochures is also a grey area. However I'm in contact with both the Dallmeyer Archive and the current legacy-owners of Dallmeyer with a view to obtaining permission to make it all freely available online via Delta.

Once the material has been photographed, and all dating clues gleaned, I sleep easy that it's preserved. What happens to the print edition becomes less relevant to my purpose.

But turning those photographs into PDFs involves labeling, straightening, colour-correcting and cropping each JPG and compilation in correct order. I could use some help with this stage of archival, which frees me to focus on gathering new source material.

[MarkWelsh]

Incidentally, I've not been contacted by the owners of the Dallmeyer Archive website with a view to fixing the errors and omissions - is anyone (perhaps privately) able to offer a lead as to who to contact? Thanks.

[pgk]

That said, one repository of information is our best chance of revealing the full picture - and it can't properly be a forum thread: there are still copyright concerns over publishing this information: when the Dallmeyer Archive was assigned the material, they were also assigned ownership of the copyright.

There is no copyright in such an archive as it has no 'artistic' content (and I'm assuming that it was UK originated). Copying such material does not produce a 'copyrightable event' either. So I'm not sure what the concerns actually can be.

[Mark J]

Righto. Will get this packed up tomorrow.

[MarkWelsh]

There is no copyright in such an archive as it has no 'artistic' content (and I'm assuming that it was UK originated). Copying such material does not produce a 'copyrightable event' either. So I'm not sure what the concerns actually can be.

As photographers we would probably argue that a photograph is artistic content - also an illustration; arguably any designed piece of print – all of which apply to brochures and adverts.

There's probably only a weak case to proscribe publication of the handwritten lens ledgers, but the holders of the Dallmeyer Archive made it quite clear to me that reproduction of their material was not permitted without explicit approval.

I agree that in most cases there's little actual risk of prosecution (no foul, no harm) from long-defunct companies. Also, even where copyright did exist, if it wasn't recently renewed it may now have expired. It's not universally clarified who is responsible for infringement - ie, the forum member, or the forum owner. I'm certainly being cautious about photographs of manufacturer's information I publish at Delta, just in case, but freely republishing all the data in it.

It only takes one complaint: look at what happened this year to decades of photographic magazine archives at the Internet Archive – gone overnight. Many of the university archives of publications like BJP have had to strip out all the adverts. It's a potential minefield, however crazy it seems - the issue isn't copying this material, it's publishing it.

The information freedom we all instinctively favour is in conflict with the protection we'd like our work to have as creators.

[pgk]

FWIW this might be of interet: https://britishphotohistory.ning.com/profiles/blogs/uk-copyright-law-clarified

I would suggest that (in the UK at least and this would apply to the Dallmeyer material), once published on the web any photographs of ledgers, etc., are effectively copyright free and trying to enforce any 'rights' considered due for ownership or 'stipulations' is never going to work as a result of copyright free copies having entered the public domain. Accordingly it is up to the owner of such material to determine whether it is copied or not and so whether it enters the public domain. Once its there its too late. As a working photographer I am very aware of © requirements but this does work both ways.

Even if older material (not necessarily out of copyright) is reproduced and published, it would be the © holder who would need to enforce their rights and anyone else would need written proof of the ownership of the copyright, not merely ownership of the material which is quite seperate from owning copyright. In the Dallmeyer case it might be difficult to ascertain whether any entity still owns copyright if any is even still in date. I doubt Cooke, who may be the most obvious descendant company, would be interested in an unprofitable enforcement.

All that said, people are strange over their perceived 'rights' in something that they own and can if they choose to do so, control the distribution of copies to some extent. My guess is that unless someone has a lot of money to burn, then they will not take any such infringement to court because of the potential cost and uncertain outcome (unlike an in copyright image which the copyright holder can impose values on infringement and go to court with a relatively clear cut case in many situations - I've had to threaten doing so myself in the past).

[Mark J]

Dallmeyer at Willesden became Avimo Optical Imaging some time in the late 80's. Avimo was then then moved to Prestatyn, and was then swallowed up by Thales Optics in 2002 and most of the staff moved to St.Asaph. This is now Exceltis/Qioptiq, where I work. I did work at Avimo in Prestatyn briefly. When I joined, Jon Maxwell said 'Welcome to Dallmeyer' !.
I don't know if there's much connection between Dallmeyer and Cooke - I can only say that Jon Maxwell ( ex head of Optics at Imperial College ) worked for both companies. Let me know if otherwise.

I can tell you for sure that the current American management of Qioptiq would not have the time or the slightest interest in worrying about some old Dallmeyer publications.

[pgk]

I can tell you for sure that the current American management of Qioptiq would not have the time or the slightest interest in worrying about some old Dallmeyer publications.

Exactly. Problems seem to occur when third parties own material and thinks that in doing so they own rights in copies of it. Its frustrating because it can limit the use of material for no good reason.

[MarkWelsh]

Dallmeyer at Willesden became Avimo Optical Imaging some time in the late 80's. Avimo was then then moved to Prestatyn, and was then swallowed up by Thales Optics in 2002 and most of the staff moved to St.Asaph. This is now Exceltis/Qioptiq, where I work. I did work at Avimo in Prestatyn briefly. When I joined, Jon Maxwell said 'Welcome to Dallmeyer' !.
I don't know if there's much connection between Dallmeyer and Cooke - I can only say that Jon Maxwell ( ex head of Optics at Imperial College ) worked for both companies. Let me know if otherwise.

I can tell you for sure that the current American management of Qioptiq would not have the time or the slightest interest in worrying about some old Dallmeyer publications.

I'll usually defer to inside information, but isn't the company you work for called 'Excelitas'? As to the following, I'm happy to be corrected if inaccurate . . .

At the risk of this getting very geeky (and dull), Dallmeyer became Watshams Electro-Optics in 1984. Watshams was bought by OMITEC Electro-Optics in 1988. In 1992 OMITEC spawned Omitec Thin Films, which was in taken over by Avimo Europe in 1997. Avimo previously (in 1975) scooped up the remants of Ross. Avimo Europe subsequently became known as Avimo Thin Film Technologies. In 2001 (perhaps concluding in 2002?), Avimo was bought out by Thales Optical Coatings. In 2008 Thales Optical became Qioptiq Coatings. After a management buyout at Qioptiq in 2008, 'Dallmeyer' became part of Artemis Optical, which in turn (last year) was bought out by G&H Holdings.

Therefore, as far as I understand it, Excelitas/Qioptiq (owned by AEA Investors) never acquired the Dallmeyer brand and therefore has no right to object - although it is in a position to adjudicate copyright of Rodenstock.

Dallmeyer's legacy came to rest in the hands of G&H Holdings. Assets of both companies were fragmented and reabsorbed over two decades, so it's not a straightfowward inherance.

Both the Brent Archive and G&H Holdings have been alerted to the possibility of publication of this information, and I'm certainly not getting the impression they're happy to allow it all into the public domain - so for the time being I'll be cautiously compliant, while working toward a better outcome that will make the data publicly accessible. Watch this space!

[Mark J]

Let me see. I should perhaps check with John on this, too.
The company I work for is Qioptiq UK Ltd which is a group of companies and a brand within Excelitas.

As regards Avimo , you have reminded me that there was Watshams, thanks.
Your paragraph above is mostly about the coatings business rather than the optics sites ; there was a branch of Avimo that did thin-film coatings that was based at Plympton in Devon and has most recently been branded Artemis, but now you are probably correct it has become part of G&H.
The Prestatyn Avimo site was probably bought by Thales in 2001 and the move was completed in 2002.
So I think I might ask John if he can add some comment about Willesden from 1980's to 1990's.

[MarkWelsh]

Thanks Mark. The parcel arrived safely this morning.
At first glance I can't date the ring-bound catalogue any more accurately than early 1960s - are you able to narrow it down?
The loose-leaf yellow pages are late-1970s: the Brent Archive has a very similar set. I need to compare them.
Are you able to cast any light on how the Glass Ticket Register was used? I'm struggling to make sense of the GJ reference numbers in particular . . .
Thanks again: I'll start work digitising them this week.

[Mark J]

Good !
I'm afraid I can't improve accuracy of your estimate of the ring-bound catalogue, sorry.
I will copy some of your comments here ( esp. regarding ownership/history ) out to John B and Jon M to see if we can improve the timeline.

Are the GJ reference numbers broadly sequential with the dates ?
If so, they are probably just an internal Optical Design reference number for each design ; in which case they would not be something that was ever marked on the product that came out. At least this is how we work on our site. The product names and serial numbers tend to come from the wider product team after the housings have been designed and prototypes assembled.

[Mark J]

John has confirmed this point regarding the glass ticket numbers :
"The Glass Ticket numbers define the optical design for the lens, not serial numbers - lenses sometimes had more than one mount configuration for the same optical design (Glass Ticket) "

[Mark J]

Re. the company history :

"My recollection is things went like this:
There was Dallmeyer that tried to revivify itself by inventing divisions like ’Dallmeyer Instrumentation’. Eventually it was bought by Watshams, whose primary business had been pylons, and became ‘Watshams electrooptics’ then OMI (Optical and medical international) came on the scene and we were renamed ‘Omitec Electro-optics’. Back in the Dallmeyer days we were pally with OEC (Optical and Electrical coatings) which was Robin Elsworth’s company. They were also bought by OMI and became OEC (‘Omitec Electro-optics (OEC)’) and then Omitec Thin Films Ltd. OMI sold its optical interests to the Avimo group and we became Avimo Optical Imaging (AOI) and they (Plympton) became Avimo Thin Film Technologies (ATFT). I guess it was during the Avimo period that we acquired our Singapore, Hungary, Germany and USA connections, though this might have begun with Omitec, I can’t remember. Alan Clarke, one time JH Dallmeyer managing director, certainly set up a German office while we were still in Willesden. Thales bought AOI with its international subsidiaries and ATFT along with Pilkington Optronics (a small optical company in a field near St. Asaph ( Ho Ho - Ed ) ) as Thales High Tech Optics (HTO) but thought better of it after a few years and Qioptiq was formed (management buy out??). After a couple of years Qioptiq ditches Qioptiq Coatings Ltd. - which is bought by the managers and renamed ‘Artemis’. Then there was Excelitas (no involvement with Artemis).
All of which is a lengthy way of saying that Artemis and hence G&H has no interest in Dallmeyer material, as far as I can see and their 200 years of heritage (link below) is tenuous to say the least. (I’d give them ~64years from when OEC was formed at most)"

https://www.artemis-optical.co.uk/our-heritage

[pgk]

I have not researched into it but I believe that the Rank Organisation (J Arthur Rank's businesses which many may know from the 'Gong sequence' at the beginning of films) bought up several British optical firms including Taylor Hobson (did Cooke derive from part of this?). Does anyone have information about which businesses were bought up and eventually spun off?

Another British optical business which has a decendant today is Sir Howard Grubb & Parsons - see: https://www.noc-ltd.com/about/company-history for a timeline.

[Mark J]

Jon Maxwell should know the detail on this. Certainly there was RTH ( Rank Taylor Hobson ) for a while, and it I suspect this eventually became the modern Cooke.

[MarkWelsh]

I have not researched into it but I believe that the Rank Organisation (J Arthur Rank's businesses which many may know from the 'Gong sequence' at the beginning of films) bought up several British optical firms including Taylor Hobson (did Cooke derive from part of this?). Does anyone have information about which businesses were bought up and eventually spun off?

Another British optical business which has a decendant today is Sir Howard Grubb & Parsons - see: https://www.noc-ltd.com/about/company-history for a timeline.

Try here: https://deltalenses.com/the-rank-family/

[MarkWelsh]

Re. the company history :

"My recollection is things went like this:
There was Dallmeyer that tried to revivify itself by inventing divisions like ’Dallmeyer Instrumentation’. Eventually it was bought by Watshams, whose primary business had been pylons, and became ‘Watshams electrooptics’ then OMI (Optical and medical international) came on the scene and we were renamed ‘Omitec Electro-optics’. Back in the Dallmeyer days we were pally with OEC (Optical and Electrical coatings) which was Robin Elsworth’s company. They were also bought by OMI and became OEC (‘Omitec Electro-optics (OEC)’) and then Omitec Thin Films Ltd. OMI sold its optical interests to the Avimo group and we became Avimo Optical Imaging (AOI) and they (Plympton) became Avimo Thin Film Technologies (ATFT). I guess it was during the Avimo period that we acquired our Singapore, Hungary, Germany and USA connections, though this might have begun with Omitec, I can’t remember. Alan Clarke, one time JH Dallmeyer managing director, certainly set up a German office while we were still in Willesden. Thales bought AOI with its international subsidiaries and ATFT along with Pilkington Optronics (a small optical company in a field near St. Asaph ( Ho Ho - Ed ) ) as Thales High Tech Optics (HTO) but thought better of it after a few years and Qioptiq was formed (management buy out??). After a couple of years Qioptiq ditches Qioptiq Coatings Ltd. - which is bought by the managers and renamed ‘Artemis’. Then there was Excelitas (no involvement with Artemis).
All of which is a lengthy way of saying that Artemis and hence G&H has no interest in Dallmeyer material, as far as I can see and their 200 years of heritage (link below) is tenuous to say the least. (I’d give them ~64years from when OEC was formed at most)"

https://www.artemis-optical.co.uk/our-heritage

That's great - thanks!

[pgk]

Thanks Mark, that amalgamates very well some of the info I had found already. So Rank absorbed a number of long established British Optical businesses, most of which vanished but am I correct in saying that Cooke are a spun off company which in effect can claim their heritage to TTH? Are there others I wonder?

[pgk]

FWIW I used to deal with one long established British optical company around 1980s who seem to have survived as an 'independant' to some degree; Beck, who made MTF test gear by then. They still exist: https://www.beckoptronic.com.

[Mark J]

Interesting . I knew them as Ealing Beck a few years ago. I didn't know that they had acquired the assets of Davin. I know the guy who was the manager and main designer Davin, and one or two people who worked there.

Thanks for the excellent link about Rank, Mark.
Hilger & Watts must have either been closed or significantly down-sized in 1968, because our long-time head of Optics at St.Asaph came up from Hilgers around that time, and I think one other designer. That was just after the Pilkington group had created PPE, across the road from the Chance Pilkington site, in a collaboration with Perkin Elmer.

[MarkWelsh]

Thanks Mark, that amalgamates very well some of the info I had found already. So Rank absorbed a number of long established British Optical businesses, most of which vanished but am I correct in saying that Cooke are a spun off company which in effect can claim their heritage to TTH? Are there others I wonder?

The article is a work in progress, and deliberately avoids telling too much of the Cooke story, which has been told elsewhere, and which I'll preçis in a different article.

But, yes, today's 'Cooke' traces its lineage directly through Taylor-Hobson, Rank Taylor-Hobson and back to Taylor, Taylor & Hobson. It might be stretching the truth to claim these lenses have been in continuous production since their inception, because when Taylor Hobson was purchased by Les Zellan in 1998, it was on its beam ends. However, by 2018, the company had been revived, rebranded as Cooke and relocated to America. In July 2018 it was sold to Caledonia Investments for £96.5m, some of which was spent on this, currently for sale:
https://www.corcoran.com/listing/for-sale/cooke-lookout-oil-nut-bay-virgin-gorda/86760526/regionId/111

[mhayashi]

Back to the original question, I have been looking up 5A and 6A sample serial numbers for two weeks recently.

I think I might finally determine what “R” means, namely Restock.

Dallmeyer used the serial number list as the stock list too, so when a lens was made, it was determined whether it was sold in advance by cash in remittance, or reserved for future sales. Dallmeyer staff wanted to mark and recognize at a glance a readily available sample to assign any restock to distinguish from new samples, so a future customer wouldn’t have to wait in line for a future production, then put the agent and customer name for the sold to column and the date of shipping.

You can now see the examples of R sequences in Dallmeyer 6A samples here.
http://thedallmeyerarchive.com/Records/Volumes/lensbook3/Portrait%20Settings/Patent%20Portrait%20Settings/A/6.pdf

The reason why 26786 doesn’t have R would imply it was determined and kept for sale to the buyer, Anthony Co. in NY in 1877.

we can also observe January 1st was when Dallmeyer made the once a year stocktaking, then the R mark is reset and is only used within one year cycle.

Dallmeyer also seemed to have the rule “the first made, the first sold” policy basically as when the previous made sample was restocked then the higher serial number sample was not sold before the lower numbered restocked sample was sold.

Or the buyer bought a secondhand sample rather than a new sample when both were available, or Dallmeyer intentionally discounted the secondhand sample, so simply it was the nature of buying the less expensive sample rather than the policy as there are cases when the newer sample was sold before the older restock sample was resold in the stock list as in here, Restock 24340 and New 24343.

http://thedallmeyerarchive.com/Records/Volumes/lensbook2/Portrait%20Settings/Patent%20Portrait%20Settings/A/4A.pdf