Me too, i have screw mount glass i don't use any more because it's too much of a hassle, and wish i could: the 105mm f2.8, the 35mm f2 and the 50mm f1.4. The night time street use i liked them for needs fast reactions and having to do manual stop down and up by pushing that stiff and inconvenient tab on the lens, takes too much time. If only Pentax had included an actuator for the auto aperture pin in those lenses...
Other than that, i can almost live with using the green button in M mode for the Pentax-M lenses. That's just an extra move with my thumb.
i haven't any problems with the optics in those old lenses, after all they're the same optics i lived with when i shot film using an SV, Tri-X and a Sekonic incident meter, using those lenses at wide f-stops that're outside of their best behaviors anyway.
So far am making do with the Tamron 17-50mm at ISO400-1000. It's kinda outside the acceptable quality zone of the K-7 tho unless i shoot in B&W ... a bit of digital bias creeping in here, no longer used to the compromises i lived with in the Tri-X/HP-5 days. Time to move up to the K-5!
One of the things i can dream of if Pentax is coming out with a mirrorless body with a new mount, is that they might have attachable mounts for it that lets me use both M glass and M42 glass with all their auto features intact. It's prolly not economically viable tho, but would be nice to mount an M lens, spin the aperture dial and see the f-stops in the viewfinder, while having the autoexposure adjust itself accordingly.
Last edited by conradj; 01-23-2011 at 07:54 PM.