what type of lens design does this set have

[baachitraka]

May I know what other lens are in the same league as dagors? Are they any book or catalog with all the info for reading...

 

[baachitraka]

Another one with no-name

 

[baachitraka]

Seller guesstimates the focal length around 140mm :-(

 

[Ian Grant]

Carl Zeiss Jena Protars are another early example of a 4 element 2 group design so only two internal air/glass surfaces.

Rudolf Kingslake wrote about Lens design and there's articles online, he became head of lens design at Eastman Kodak in Rochester and was responsible for the top end Commercial Ektars etc. For a modest fee you can download "A Lens Collector's Vade Mecum" which is a useful but no longer updated resourrce listing manufacturers and their lenses.

A bit of practical experience using older lenses goes a long way, it's fine reading that some old lenses have better contrast than others, that some lenses like Dialytes may be sharper and better at all distances but have lower contrast if not coated, and be aware first hand just how much difference coatings make to both contrast and flare.

I've tested lenses in the 120mm to 165mm range on bellows with a DSLR essentially to test the contrast. It's also worth noting that pre-WWII photographers worked a different way, films/plates were given more exposure and developed for longer to a higher density and contrast but printing papers matched, am POP papers are self masking which helps as well. It was Leica users and writers like Hans Windisch in "Die Neu Foto Schule" who pioneered our modern approach of optimal exposure and development to achieve finer grain, better sharpness and a longer tonal range (better shadow detail), helped by the advent of the first exposure meters. Gossen advertise in Windisch's book, along with Leitz, Exacta etc, it wasalso published in English as The New Photo School) and later updated after WWII to become "The Manual of Modern Photography - The Technique".

Ken Lee has some interesting papges on using older lenses on his website particularly Tessars.

I think DAn Fromm's mantra of what's a lens like "Ask it" in terms of try it yourself is the best approach.

Ian

 

[choiliefan]

Are all Dagors 6.8?

 

[Ian Grant]

Are all Dagors 6.8?

No some were f7.7 and the WA version was f11.

Ian

 

[baachitraka]

Are all Dagors 6.8?

I was bit sleepy and miss-took the question as, Are all 6.8 Dagors? :-(

 

[baachitraka]

Are there any coated lens that were fitted to plate cameras then?

 

[Ian Grant]

Are there any coated lens that were fitted to plate cameras then?

Well yes and no, CZJ and TTH came up with coatings in the late 1930's, TTH coatings were deemed a Military secret in the UK but there's little to no data about how they were used until after WWII..

CZJ coated some higher end camera lenses from 1938 onwards, but only a few like 150mm f4.5 Tessars and I think 50mm Sonnars, and that wasn't every lens, So yes you could have a coated 150mm Tessar on a pre WWII plate camera -just.

Post WWII there were still plates in use, so it depends what you define as a plate camera. A Linhof Technika or MPP Micro Technical is derived from the metal bodied pre WWII plate cameras and plate holders were available (I have 30 or more MPP plate holders). Gandolfi still offered book form style backs and holders well into the 1960's and they used plates not film and of course post WWII LF lenses were coated.

I've seen a 1938 150mm T (coated) Tessar for sale and the coatings were the same as my 1953/4 T (coated) 150mm Tessar.

Ian

 

[baachitraka]

Well yes and no, CZJ and TTH came up with coatings in the late 1930's, TTH coatings were deemed a Military secret in the UK but there's little to no data about how they were used until after WWII..

CZJ coated some higher end camera lenses from 1938 onwards, but only a few like 150mm f4.5 Tessars and I think 50mm Sonnars, and that wasn't every lens, So yes you could have a coated 150mm Tessar on a pre WWII plate camera -just.

Post WWII there were still plates in use, so it depends what you define as a plate camera. A Linhof Technika or MPP Micro Technical is derived from the metal bodied pre WWII plate cameras and plate holders were available (I have 30 or more MPP plate holders). Gandolfi still offered book form style backs and holders well into the 1960's and they used plates not film and of course post WWII LF lenses were coated.

I've seen a 1938 150mm T (coated) Tessar for sale and the coatings were the same as my 1953/4 T (coated) 150mm Tessar.

Ian

Something similar but its f/3.5

 

[Ian Grant]

I bought my T coated 150mm f4.5 Tessar as lens cells on this Forum, with no shutter, it dates to the point where Linhof switched from CZJ Tessars to Carl Zeiss, West German, Oberkochen lenses. Ironically I was given a Linhof 150mm f4.5 Carl Zeiss Tessar by a member here 3 or 4 years ago for the cost of postage (from Australia) because it wasn't sharp, it's near mint condition and won't focus.

You can get an idea from the reflections that the coatings are significant compared to teh uncoated 135mm Tessar on teh right.

The lens you've shown will be quite large needing a Compur #2 shutter I think and Deckel hadn't made the Rimset #2 at that point 1938/8, looks to be a 2.4**,*** Serial Number. I know it's relative size as I have a 135mm f3.5 Tessar on an Ihagee 9x12 camera.

Ian

 

[AgX]

CZJ coated some higher end camera lenses from 1938 onwards, but only a few like 150mm f4.5 Tessars and I think 50mm Sonnars, and that wasn't every lens, So yes you could have a coated 150mm Tessar on a pre WWII plate camera -just.

Zeiss themselves in their recent treatise on that matter stated that up to 1940 only "military optics" (whatever that means) were allowed by governmental order to be coated. Only as late as 1940 "photographic lenses" (Sonnar and Biotar) were presented, and from then on seemingly only a few models were coated, for sure the Sonnar 50mm 1.5 .

 

[Ian Grant]

Zeiss themselves in their recent treatise on that matter stated that up to 1940 only "military optics" (whatever that means) were allowed by governmental order to be coated. Only as late as 1940 "photographic lenses" (Sonnar and Biotar) were presented, and from then on seemingly only a few models were coated, for sure the Sonnar 50mm 1.5 .

That's at odds with a handful of lenses I've seen and also Carl Zeiss adverts here in the UK in the British Journal Photographic Almanacs, Of course the lenses may have been military and liberated after the end of the war, but the adverts do say different. I've seen two 1938 T coated f4.5 150mm Tessars and adverts state the 50mm Sonnar was available coated.

In the build up to WWII a lot was kept secret, Here in the UK there was no apparent build up of engineering facilities for military production. However all the major car manufacturers expanded to second or third sites, so called shadow factories. It explains why Ford, Austin, Morris, Rover/Land Rover, Jaguar etc had two plants after the war the shadow factories were earmarked for rapidly expanding military production.

Where I live Carpet factories were given new machine tools and expanded their own engineering facilities, it was all secret. Different ways of secrets.

Ian

 

[lobitar]

No some were f7.7 and the WA version was f11.

Ian

Pardon - but I thought the old f.11 was more like a repro thing, while the WA's are f.9 (older) or f.8 (newer)?

 

[Europan]

However all the major car manufacturers expanded to second or third sites, so called shadow factories.

Same goes with National Optical Co. of Leicester to Taylor, Taylor & Hobson.