Week 6: C.P. Goerz Dopp.Anastigmat 4.5/90
There is not much to find about this lens in the internet. I got it from a photo friend and converted it to an EOS mount by using M42 belllows and an M42-EOS-adapter.
It works pretty well like this but, of course, it cannot be used like a new lens. Handling is slow and you need to be careful to focus correctly. Anyway, it’s fun to use such a lens on a modern DSLR body.
The images it produces are, due to the lack of coating, low in contrast but they show a nice “glow” at the highlights. Contrast is corrected easily in post production but that glow cannot as easily be produced if you want it, it’s a character of the lens. Old Leica lenses also are famous for such a glow and they have a huge fan comuunitiy exactly because of that.
Another photo friend of mine, from Budejky, Czech Republic, wrote: “Double-anastigmat and f/4.5… well, with the exception of super-exotic designs there are only 2 possibilities: it could be double-gauss lens or dialyte (currently better known as helioplan). I know Goertz used dialyte design under name “Dogmar”.
Anyway, both double-gauss and dialyte have 6 inner air-glass surfaces. That’s too much for uncoated lens – according to many collectors 2 inner air-glass surfaces produce good contrast (protar, dagor, ernon), 4 air-glass surfaces produce acceptable contrast (e.g. triplets, hektors, heliars, or early sonnars) and 6 air-glass surfaces are on the low side (double-gauss, dialytes – dogmar, helioplan, veraplan, unofocal…, planars) […] old uncoated Helioplan – I think it will produce very similar images to your Goertz lens.”
Thanks “no-X” for that explanation.
Here are some (older) images I have taken with this lens on the EOS 5D:
If anybody knows more about this lens, please send me an email. I’d be grateful for any imformation.
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