The above information applies only to lenses which are in good condition, properly centered, and properly mounted. Every Dagor I've ever had, from early Berlin production to the last MC Kern version, was diffraction limited in the center by f:16 to f:22. Yes, it will illuminate more, and even a 210 with dark corners on 8x10 will still have contact - printable details in said corners if you hold them back, but if you are enlarging full negatives 55-60 degrees is the limit for real sharpness and detail.Ĥ) Sharpness. 55 to 60 degrees is about the limit, depending on vintage and manufacturer. The Dagor is not capable of covering the 80 or so degrees it is reputed to. f:16 is a real sweet spot for most Dagors, and wider apertures may be good for portraits I prefer a 161/2" Artar so I don't know for sure.ģ) Coverage. As you stop down, the lens grows sharper, gets longer, and gains contrast up to about f:16. At maximum aperture there is a fair bit of veiling flare due to uncorrected spherical aberrations. So, refocus at working aperture.Ģ) Aberrations. As you stop down, most if not all Dagors get longer i.e. Especially on the internet.ġ) Focus shift. Goerz Dagors are a lot like Nikola Tesla and Jesus in that they are very often ascribed virtues and accomplishments they do/did not possess. It's very hard to see differences between coated and MC lenses, but the differences between coated and uncoated lenses is very noticable with designs like Tessars, and even more so with Dialytes, but with Dagor & Protar (and type) lenses it's the opposite even un-coated they are so close to an MC lens.
However we have to remember uncoated lenses are old mostly pre WWII and unless in excellent optical condition other factors will play a part, scratches, separation, haze, fungus etc. I don't use the term Single coated because many/most have 2 or more but aren't Multi-Coated to the standard set by Pentax an Zeiss Dan Fromm made me question and try coated. I was a long term advocate of only using MC lenses after poor results from some 35mm lenses inc MC Hoya (the range was scrapped). You should try to borrow or test an un-coated Dagor. I think your last sentence is one not really considered, it's not one that bothers me as I've only been shooting B&W (film) for most of the past 30 years, any colour work has been with MC Plasmats, Sironar N, Symmar S.
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