Old Caltar Type-S 150mm - what is it?

[Steve Goldstein]

I picked this up for next to nothing, in its original box. It has beautiful rainbow-colored separation in both front and rear cells. The Synchro-Compur 0 runs a bit slow.

It's marked Calumet Caltar Type S - 150mm, 150mm, f/5.6, in a Synchro Compur size 0 shutter. Its serial number is 6306253. The caps are 70mm front (67mm filter thread), 42mm rear. It's not marked as a convertible lens, there's just one aperture scale indicated.

The physical dimensions don't match any of the Schneider literature I've got for old Symmar or Symmar-S lenses, but the box is marked "Made is West Germany". I'm guessing it must be a mid-60s original Rodenstock Sironar, which I seem to recall are prone to separation. Can anyone confirm or refute my guess? Any comments as to its optical merits or lack thereof?

I plan to use it as my learning vehicle for recementing. Some day....

[David Karp]

Hi Steve,

The following information is from Kerry Thalmann's article Caltar Lenses: Past and Present from the May/June 2003 issue of View Camera. A Caltar Type S is, as you supposed, a Rodenstock Sironar. The image circle is 208mm. According to Kerry: "This was intended as a premium line to enhance, but not replace the Ilex-Calumet Caltar line."

[David Karp]

I forgot to mention that article also lists the filter size for the 150mm f/5.6 Caltar Type S lens as 67mm.

[Oren Grad]

Plain Sironar, indeed. As far as optical merits, quite a few years back now I had a 300 mm Caltar Type S briefly - Calumet itself mistakenly sold it to me as a used Caltar II-N! - and although it was basically competent in projecting a sharp plane of focus, as pretty much any modernish 300 plasmat will be, it didn't have the refined focus transition and background OOF rendering that was introduced in the Sironar-N generation and further developed in the Apo-Sironar-S. I returned it.

[Steve Goldstein]

Thank you both for confirming my suspicions. I'd forgotten about Kerry's article, I'll have to go dig it up and justify to my wife keeping all those piles of old magazines

It sounds like this will be a perfect candidate for lens recementing school. With luck it's just balsam and won't require heroics of chemistry to disassemble.

[Fotoguy20d]

I really doubt it's going to be balsam.

Dan

[David Karp]

The aforementioned article describes the era of the Caltar Type S as 1970-76. Were manufacturers still using balsam then?

[David Karp]

You might find some useful information here, although it is a bit like watching a car wreck: http://www.largeformatphotography.in...ens-separation

[David Karp]

This article indicates balsam was used prior to 1946, for what it's worth: https://www.optical-cement.com/cemen...al/manual.html