> I saw a Pentax 500mm screw mount lens on eBay, I can buy it for $100, but > it's not a Takumar. On the other hand, it's not a mirror lens, and it > has an adjustable aperture. How is the non-Takumar 500mm?
All of the PENTAX brand 500mm screw lenses were Takumars. It probably was a third party lens. The good 500mm Pentax screw lens is the 500mm F4.5 > > Looks like a reasonable collection of lenses would be > > 28mm (are there multiple varieties?) > 50mm or 55mm in f/1.4 or f/1.8, either macro or not macro > 135mm f/2.5 > 300mm f/4.0 > > At least I have the last two figured out. What I'm looking for in the > other two is good optics more than options. For instance, if that means > 50mm without macro then that's what I would want. Do you know the > different lenses in that kind of detail? > > And how's the 150mm versus the 135 f/2.5? I guess I only need one of > them, and again my choice would be the better quality optics versus a > small advantage in telephoto or aperture. > The 150 is F4, about a stop and a half slower than the 135 2.5. It's really only usable in bright sun. Not true for the 135 2.5. The 150mm SMCT F4, is quite scarce indeed, but the 150 Super-Tak is probably just as good and way easier to find. JCO
