practical coverage of 6.5" W.A. Dagor?

[John Koehrer]

yep, that's it.

[Dan Fromm]

John, have you looked here http://www.cameraeccentric.com/html/info/goerz_3.html ? Goerz makes the same claims in the 1940 catalog too.

I don't know whether catalogs' claims can be trusted but they're probably safe upper limits, i.e., might cover less than claimed, for sure won't cover more.

We should all check Seth's catalogs, he has a nice collection with, of course, gaps that is on the whole, very useful. Some of them have got me into worthwhile trouble.

[William Whitaker]

I just put my 6 1/2" WA Dagor on the 10x12 and found that the image appears to just clip the corners at infinity focus and wide open (ƒ/8). It's an overcast day and not a lot of light, so judging dim corners is difficult. I focused a bit "beyond" infinity and it appeared to clip a little more, so I think I could probably use this lens straight-on 10x12 wide open at infinity and at worst I might have to trim about 1/8" off each side of the print. Maybe not, but I'm being conservative.

But please note the difference between circle of illumination and coverage. I was not able to judge the drop-off in sharpness visually; that's better done on film. I used this lens (or one like it) on 8x10 several years ago and was very pleased with the results. The images were sharp and clear, although the critical image area was mostly toward the center of the field, the edges being occupied by sky. I think for 8x10 the lens is probably fine and would even offer a small bit of movement. But it would depend partly, too, on your subject matter and compositional style.

FWIW,
~W

[John Koehrer]

Thank you,
I had looked at the Goerz charts but didn't know how much faith to put into them.
I've got one in the classifieds & was asked this question.