Hi, I have RBproS with Sekor C 127/3,8 lens. Now, as my brother will go to USA in June, I plan to to buy some lenses. I know this kind of question was asked several time before, but I am particulary interested in my second question, as I never was 100% shure if I understood that issue correctly. So, my questions are: 1. As I understand ALL RB lenses/bodies are compatibile (I mean lenses for RB are compatibile with RBproS, and lenses for RBproSD are compatibile with RBproS). Is that true? 2. I have heard (read) that some of the RB lenses must have some Mamiya adapter to be able to be mounted on RB bodies. Is that true, and if it is what lenses must have adapter to be mounted on RBproS body? My plan is to buy 65mm, 180mm, and will see depending of avaliable money maybe 150mm SOFT and/or 250mm. I am not into macro work, so I don't think 140mm MACRO will be in my plan... I also plan to buy some light shade(s) for lens(es). What is good, and is comprendium worth of buying? Does is fit to all lenses (diameters)? I will tell my brother first to look at KEH. What are other worthly sources? Any other advice will be appreciated. Thank you.