Sinaron S 135mm f5.6

[Nigel Richards]

Hi,
Last week I bought a Wista 45dx in very nice condition with a lens mounted in a very home made lens board. I have now remounted the lens in a Wista board.
The lens has engraved on the outer edge of the front lens set "Sinaron S 72 degrees 1:5.6 f=135mm MC Sinar" it is mounted in a synchro-compur shutter, it was effectively thrown in with the body! A bit of searching on this forum explains that it is actually made by Rodenstock and re-badged for Sinar.
The reason I am posting this question is because I can't find a similar lens on the internet that looks the same. So is my lens genuine, if so is it true that Sinar picked the best Rodenstock lenses to be Sinaron S lenses or is that simply a well repeated myth? I guess even if this isn't true it should be a good performer ?
Not yet had the time to try the camera and lens in anger so everything is currently theoretical!
Photo of the lens attached.
Thanks
Nigel in the UK
ps My other camera is a 5x4 Nagaoka Seisakusho

[koh303]

Sinaron S = Apo Sironar N (rodenstock), in this case, a slightly older version, but only differs from newer ones by the way its marked.