I am shopping for a used 300 f/5.6 lens for 5x7. I lean toward Rodenstock since my other five lenses are all that make. But I am open to a good deal on a Schneider. I have come across several Rodenstocks on eBay. For some reason, the 300 focal length is really pricey. Compared with other expensive used Rodenstocks, such as the 115 f/6.8 Grandagon-N or 90 f/4.5, the used prices for 300 5.6 lenses seem really high.

Anyway, I have found two of particular interest:

-An Apo-Sironar-N asking $1,100
-An Apo-Sinaron-S asking $850 (the version made for Sinar)

The Sinar version does not have the gray ring like the Apo-Sironar-N does. This leads me to believe it may be a 1980s lens, as I think the gray, red, and yellow rings denoting the N, S, and W series Rodenstock lenses came along in the 1990s.

The N-series should work fine for me, since I am shooting 5x7 and won't need the extra coverage afforded by the S and W lenses. The main thing I want is the best possible sharpness and contrast, especially wide open at f/5.6. I have been using an Apo-Ronar f/9 for years and I love the sharpness at close-to-medium distances, but I want the shallower depth-of-field, brighter focusing, and increased movements at infinity of a 300 f/5.6.

Any advice would be appreciated. Thanks in advance.