Originally Posted by MacDaddy
I find it interesting in reading this discussion that no one has pointed out that several manufacturers, including Canon and Nikon, but most noteably Pentax, have trumpeted the fact their older FILM designed lenses apparently work quite well with their DSLRs. I had a Pentax ist DS prior to switching back to film and was able to successfully use lenses as old as 35 years old with the proper adapters! Some of their prime Limited series lenses are outstanding, and this on an APS-C size sensor. The only "curse" was the blasted crop factor (1.5x), but it was liveable with for me.
I agree with you - I bought the Pentax *ist DS myself, for the same reasons. I use even older lenses - Carl Zeiss M42 lenses, old WWII German lenses, etc. I also use the very nice Pentax SMC M42 primes, and here lately, the Pentax SMC-A P/K mount lenses (nice for auto-everything-but-not-AF). I love 'em!
I finally broke down and got myself an inexpensive Sigma 28-105 ASP f2.8~4 AF zoom, and a Sigma TTL flash. Great for speed.
As you said, Pentax has really done a bang-up job of providing backward compatibility. And I'm a long-time Canon FD fan, I'm new to Pentax.
I did a lot of searching and study before buying. The Pentax *ist DS was superior to the Canon Digital Rebel for the purposes I wanted to use it for. I'm happy with my choice.