Rodenstock 180mm f/5.6 Sironar

[Bob Fowler]

I recently bought yet another Toyo monorail (a D45M this time) via that famous on line auction site. Included with the deal was a Rodenstock 180mm f/5.6 Sironar in a #1 Synchro Compur. I cleaned the slow speeds escapement which got the shutter working correctly and shot some test images. The end result, I like the lens.

There is a ton of information about the Sironar-S and Sironar-N available, but I can't seem to find anything about the plain old Sironar. Can anyone clue me in as to the design of the lens (elements/groups) and other specs such as coverage angle and image circle?

TIA

[Michael S. Briggs]

The plain Sironar is the predecessor of the current Apo-Sironar-N and Apo-Sironar-S lenses. "Sironar" is the name that Rodenstock uses for their plasmat-type lenses, which have 6 elements in 4 groups. The Sironar is approximately contemporaneous with the plain Symmar, and like that lens was marketed as being convertible -- by removing one of the cells, you get a longer focal length lens, but with reduced image quality.





You can estimate the age of your lens from the table at Kerry Thalmann's website: http://www.thalmann.com/largeformat/agevs.htm.

[Bob Salomon]

"The plain Sironar is the predecessor of the current Apo-Sironar-N and Apo-Sironar-S lenses."

No.

The predecessor of the Apo Sironar N was the Sironar N MC. It's predecessor was the Sironar N. It's predecessor was the Sironar. Several decades and 2 variations that were not convertible lay between the Sironar and the Apo Sironar N.

There was no predecessor for the Apo Sironar S.

[Bob Fowler]

Thanks for the help guys. Regardless of its heritage, it's a keeper in my lens collection!