Quote Originally Posted by PentaxBronica View Post
They made it from 1975-77 in the original SMC Pentax series of K mount lenses, it's not particularly common as it would have been pretty expensive and most people would have just bought a 135mm prime to go with their 50/55mm kit lens. It apparently carried on from '77 until '84 with lower-case "smc" rather than "SMC" on the rim, there are also some with and some without an additional focus scale to be used with the matching close-up lens.

I didn't realise that it was one of the lenses which survived after the rest of the K series lenses were withdrawn. There were a small handful, some of which had new finishing rings with "smc Pentax-M" instead of the older SMC Pentax and some of which just got the lower-case smc lettering. I usually try to stick to the original K lenses as they hold their value well and suit my preferred bodies (either a KX, K2, or M series with a winder for balance).

There was an SMC Takumar version too for those using either screw mount bodies or other systems with an adapter.

Most, most educational. And I still want one!!
Actually, it's a long time ago isn't it? I didn't start out in photography until 1979 (with, of all things, a Russian Zenit E, which my dear dad objected most severely to: "bloody communist crap! Take it back and get a refund, now please!". I did that. Came home with an Olympus OM10.)