Mamiya RB Lens - C vs non C

There is a considerable amount of debate on the RB C or non-C lens. I

have a 127mm C and love it. I want to add a 180mm but to go with C is

out of my price range. I do not use the RB all the time, but the 180

would be helpful. What is the real difference in the lens other than

about $100-$200? I know the non-C is not fully multi-coated. Is that

the main difference? What about repair? I would like the 180mm C.

but money is an object and I do not use the RB all the time. Any help

would be appreciated.

As you noted, the C lenses are multi-coated, while the non-C lenses are single-coated, making them more prone to flare. For the most part, that can be overcome by using a good lens shade.

The other difference should cause you more concern; in general, the non-C lenses had shutters for which repair parts are no longer available. I said "in general" because I understand the newer shutter may not have come out at exactly the same time as the multi-coating. It's never been clear to me whether some C lenses have the older shutters, but that's the feeling I have from what I've read. There is no problem if the shutter just needs a CLA, but if it needs parts, the only option is to have the shutter replaced by one of the newer style, at a cost of $400. You have to decide whether initially saving $100-$200 is worth the risk of such a repair bill.

Get the 180 C, even a used one if you can find one. I have a 180 C and the superb optical quality of this lens is the only reason I don't take my RB out out to the gun range and use it as a target.

The older 65 and 90 "C" lenses are to be avoided.