210 lens question.

[ChuckMartin]

Hi i'm just getting into large format and came into two 210mm lenses. A Caltar-S II 210 f5.6 and a Caltar HR 210 f6.8. Can anybody tell me the difference between the two? Is one better than the other? Sharper? Wider coverage?

Thank you.

[Luis-F-S]

I would get the one that's better priced. The f5.6 will have a larger image circle which may or may not make a difference. I really doubt you'll be able to see any difference in sharpness once stopped down.

[fishbulb]

Caltar lenses were manufactured for Calumet by various manufacturers.

The Caltar-S 210 is going to be a multicoated Schneider Symmar-S (probably not the older convertible Symmar design, where you can take the rear element off for a longer focal length - it would say so on the lens or shutter if it was convertible, and probably wouldn't be a "II" lens, as the II indicates multi-coated and the Symmar's were single coated (vs. the Symmar-S which was multi-coated).

The Caltar HR 210 is likely a Rodenstock Geronar 210 f/6.8 underneath. It is a multi-coated 3-element lens that was a "budget" lens. Not that it's bad, just a lower price point.

Personally I would go with the Symmar-S. A bit bigger, heavier, but a more complex optical design (6-element plasmat) and a wider maximum aperture (brighter ground glass). The Geronar is a good lens, lightweight, but a more simple 3-element triplet design, and not as sharp at wider apertures. At f/16 and smaller apertures, you won't see much difference, but I would still give the performance advantage to the Symmar-S if I had to bet on it - mainly due to the Symmar-S' larger image circle.

There is some testing of the Geronar here, but not the Symmar-S, just the older Symmar convertible design: http://www.hevanet.com/cperez/test/BigMash210.html

The coverage of the Geronar is 240mm at f/22, or 230mm (http://www.largeformatphotography.info/lenseslist.html) depending on what source you believe. For the Symmar, it's 294mm at f/22 (https://www.schneideroptics.com/info/vintage_lens_data/large_format_lenses/symmar-s/data/1,5,6-210mm.html).