Coverage of DAGOR 1:6,8 f=21cm?

[abeku]

Dear all,

I'm interrested in the coverage of a Dagor lens. Anyone out there that has experience of this Dagor 6,8/210?

Thanks,

 

[Ian Grant]

Here's the information

Dagor lens

5"x8" at f6.8
7"x9" at f16
12"x12" at f45

I use a 300mm Dagor and it's superb.

Ian

 

[Dan Fromm]

Search. Dagors' coverage has been discussed many times here and at http://www.largeformatphotography.info/lfforum/ .

Short answer, manufacturers of f/6.8 Dagor types -- Goerz wasn't the only one -- typically claim 85 degrees "stopped well down," i.e., at f/22. One of my friends who did optical calculations for Boyer tells me that this is a gross exageration. He says that 70 degrees is all one can count on, 50 degrees for really critical work, i.e., in process cameras. Yes, Boyer made a Dagor type.

 

[abeku]

Many thanks for the prompt replies! That information was exactly what I needed. I wasn't aware that the coverage differs that much when stopped down. Can also different shutters (their contruction) affect the coverage as well, i.e. physically restrict the coverage?
Dan, I always do a search before asking! However, I'm very novel to LF and all the gear out there and therefore the threads are sometimes not that easily to follow.

 

[Ian Grant]

If the lens is mounted in a shutter this has no effect on the lenses coverage.

Ian

 

[Ole]

If the lens is mounted in a shutter this has no effect on the lenses coverage.

Unless it's front-mounted - some barrel lenses are sometimes mounted on the front of the shutter, since it's too difficult to mount them normally. This can limit the image circle.

But that is not the case here, so there's no need to worry.

 

[abeku]

Once again, thanks! I'll go ahead and bid on this Dagor lens!

 

[matti]

Oh no! I spotted it first!
Guess should continue playing with my new Heliar instead of fighting over that one...
/matti