Re: K135/2.5 vs FA 135/2.8 (was Re: Vivitar 135/2.3 lens ?)

[Caveman]

I just visited Boz's site and it mentions a 5-5 design for the K 200/4 
(which is also a nice lens I'd say), so I suspect that Fred is reffering 
to the A 200/4 (which is one of the lenses that I don't hear much about, 
it's not very popular or rare or something).

Fred wrote:
The K 135/2.5 is also one of only three Pentax lenses that have the
same optical design (according to lens element diagrams) - the K
135/2.5, the K 200/2.5, and the A* 200/2.8.
(Note that it's not just the "6 elements in 6 groups" configuration
that they share - it's also that their optical diagrams are
virtually identical.)  (The K 200/4, as a contrasting example, also
has a "6/6" formula, but has a different optical diagram.)