Douglas Stemke , Feb 18, 2005; 03:34 p.m.
First I'd highly recommend the Pentax primes, they are generally beautiful lenses. There are several different A and M (even a K) 50mm lenses. You can check them out at
I have personally used the following:
M f1.4 A f1.4 A f1.7 A f2.0
Depending on what your needs are there are advantages to each, although I personally least like the M. The f2.0 A is super light, super cheap and not a bad piece of glass. The A 1.4 is super fast, pretty heavy (for a normal lens) a real joy to use in museums or indoors if you don't use flash. If you plan to reverse the lens for macro work stay away from bioth f1.4.
The 50mm f1.7 A is very light (although not as light as the f2.0) naturaly very fast, and is one of the best lenses Pentax has ever made-in optical tests it is only surpased by Pentax's 50mm f2.8 F macro.
I can't comment on the Richo other than it is obviously slower than the f1.7 and f1.4s. However Pentax normals are some of the best lenses ANY company has ever made so I don't think you can go wrong with any of the Pentax lenses.