Interesting Goerz Dogmar 5"

[gorbas]

Does anybody knows specific purpose of this lens?
Goerz Dogmar F:4.5 / 5"; Pat. Aug 25, 1914, barrel lens, no iris, mount- imperial thread 1-25/64" or 35.28mm
Thank you in advance!

 

[Ian Grant]

1914 and US made possible some type of military use. When WW1 broke out the US CP Goerz company severed it's ties with CP Goerz, Berlin, they were already Independent in legal terms but here you have two sons by then US citizens running the US side and supporting Britain and the allies and their father and his company supplying the German military.

Dogmar's are dialytes so 4 air spaced elements, I'm not sure what the fastest German Dogmar was, I have one of the same approx age and it's f6.8

Ian

 

[JPD]

Dogmar's are dialytes so 4 air spaced elements, I'm not sure what the fastest German Dogmar was, I have one of the same approx age and it's f6.8

The fastest Dogmar I have seen is 3,5 and the slowest 6,3. Are you sure yours isn't a 6,3?

 

[Dan Fromm]

The fastest Dogmar I have seen is 3,5 and the slowest 6,3. Are you sure yours isn't a 6,3?

(1) The lens is engraved 4.5
(2) Look in the VM
(3) I doubt you've seen everything that exists.

 

[JPD]

(1) The lens is engraved 4.5
(2) Look in the VM
(3) I doubt you've seen everything that exists.

If you find a Dogmar that is faster than 3,5 or slower than 6,3 it must be very rare. The 4,5 version is the most common.

 

[Dan Fromm]

If you find a Dogmar that is faster than 3,5 or slower than 6,3 it must be very rare. The 4,5 version is the most common.

That's what the OP has. Please see post #3 above, in which you suggested the OP's lens might be f/6.3.

 

[JPD]

That's what the OP has. Please see post #3 above, in which you suggested the OP's lens might be f/6.3.

No, I was replying to Ian's post.

 

[Dan Fromm]

No, I was replying to Ian's post.

Thanks for the clarification.

 

[JPD]

Thanks for the clarification.

Well, I clearly quoted Ian. Your snarky comment felt out of place.

 

[Ian Grant]

The fastest Dogmar I have seen is 3,5 and the slowest 6,3. Are you sure yours isn't a 6,3?

Just checked yes of course it's a 135mm f6.3 as is my 135mm Goerz_Ihagee Dopp. Anastigmat - also a Dialyte but not identical. An f3.5 Dogmar must be quite a large lens, my 135mm f4.5 Eurynar is in the older Dial set Compur 2, I'd expect a 135mm f3.5 Dogmar to be in a Compur 3.

Ian

 

[gorbas]

Thank you Ian! As always! Right on dot!
Thank you all for contributions!
Its fairly low contrast lens and comparing with SLR TTL and with other trusted lenses, it is f4.5
I have one similar FL Eurynar in shutter and will compare them sometimes

 

[Ian Grant]

Back in the day uncoated Dialytes were in common use films were over exposed compared to today's use and also developed to higher contrasts and density. But quite strong Pyro developers were also the norm and they tend to be self masking, the higher the density the more stain and the more tanning slowing development of the highlighrs. PApers of the time matched those negatives and helped overcome some of the lower lens contrast

A few years ago I did a test with a few lenses 120mm to 165mm all in excellent optical condition, the DAgor had no contrast drop compared to a modern lens, a Tessar a slight drop and a Dialyte the Goerz-Ihagee mentioned above had quite low contrast, a Meyer WA also 4 air spaced element was the worst. All down to the number of internal air/glass interfaces.

Sharpness is different a Dialyte can be superb and from 1:1 to Infinity, the coated 203mm f7.7 Ektar is a fantastic lens, if you find one in a Compur they are the best, Compur #1 US made, Compur #0 UK made

I think it's Ole on this Forum who has a post WWII coated Eurynar but I think they are rather rarer. I used Foma films with my Eurynar because of their inherent contrast but I had issues with the plate holders (with film inserts).

Ian

 

[lobitar]

Back in the day uncoated Dialytes were in common use films were over exposed compared to today's use and also developed to higher contrasts and density. But quite strong Pyro developers were also the norm and they tend to be self masking, the higher the density the more stain and the more tanning slowing development of the highlighrs. PApers of the time matched those negatives and helped overcome some of the lower lens contrast

A few years ago I did a test with a few lenses 120mm to 165mm all in excellent optical condition, the DAgor had no contrast drop compared to a modern lens, a Tessar a slight drop and a Dialyte the Goerz-Ihagee mentioned above had quite low contrast, a Meyer WA also 4 air spaced element was the worst. All down to the number of internal air/glass interfaces.

Sharpness is different a Dialyte can be superb and from 1:1 to Infinity, the coated 203mm f7.7 Ektar is a fantastic lens, if you find one in a Compur they are the best, Compur #1 US made, Compur #0 UK made

I think it's Ole on this Forum who has a post WWII coated Eurynar but I think they are rather rarer. I used Foma films with my Eurynar because of their inherent contrast but I had issues with the plate holders (with film inserts).

Ian

Thanks for the interesting insights.
I own a Rodenstock Eurynar 18cm 6,8 brass lens from abt 1915-18. I've shot some 4x5 Ektachromes on my Sinar that I like a lot and think perhaps would be acceptable to most as for sharpness and contrast.