Are these the same as the Sironar-S per focal length? I posted this over in the LFPhoto forum also, though no response as yet. There seems to be MUCH evidence to suggest the Sinaron's are remarketed Sironar S's. But I'd like to know if anyone has any real info (insiders) - I'm sure SinarBron and HP Marketing would both deny it, of course, since the Sinaron was marketed to be designed specifically for a 3x3cm sensor - which is pretty funny, since the 135 I have has an identical image circle to the Sironar-S.