It isn’t a secret that Sinar-branded lenses are made by Rodenstock. I have one and the fine print on the lens says “Made by Rodenstock”. Looking at Sinar’s descriptions, and especially Sinar’s specifications, the following identifications can be made:
| Sinar name | Rodenstock name |
|---|---|
| Sinaron WE | Apo-Grandagon |
| Sinaron W | Grandagon-N |
| Sinaron S | Apo-Sironar-N |
| Sinaron SE | Apo-Sironar-S |
| Sinaron WS | Apo-Sironar-W |
| Macro Sinaron | Apo-Macro-Sironar |
| Apo Sinaron | Apo-Ronar |
The Rodenstock is currently made and you can download a PDF file with its specs, according to Rodenstock, from http://www.rodenstock-photo.com The Schneider is no longer made, replaced by the Super-Angulon-XL and the f6.8 “Classic”. Schneider has specs on their older lenses at including the 90 mm f5.6 Super-Angulon at http://www.schneideroptics.com/info/vintage_lens_data/ , (link)
You can look up the age of the Schneider using the table at http://www.schneideroptics.com/info/age_of_lenses/index.htm .