I just picked up a used Rodenstock Sironar-N 210mm lens. It's aperture range is f45.6 - f45 and has "MC" stamped on it which I assume stands for multi-coated. I t has a serial number of 10332697.

I'm assuming this is an older version of the APO Sironar-N series. Can anyone ou t there in large format land confirm my older version theory and let me know a l ittle more about the lens?