First, I cannot believe that this thread is still going on. The point, Paul, was very simple. A while back there was a discussion about using screw mount lenses on the Pentax DSLR cameras. So, one day I had the ST 105/2.8 handy, and the istDS was close by as well. It seemed like a good experiment to see how well the lens could be focused with that camera, and what the limits were. Perhaps if the lens could be focused accurately and easily at shooting aperture, there may be some advantage for street shooting. And since ST and SMC Tak lenses can be had rather inexpensively, it seemed that, if the lens could be easily and accurately focused at shooting aperture, people on this list who were on a tight budget, or who read favorable comments about using screw mount lenses on the DSLR's, might be interested.
I was somewhat surprised at the results, and posted them. The test was such that I didn't just sit in the office and focus on something. I went out into the neighborhood and shot about fifteen or twenty frames, in varying light and in different circumstances. Close objects, scenes at infinity, and so on. In every case the 105/2.8 was easy to focus, and provided accurate focus, at f4.0, 5.6, 8.0 and even at f11. For a street shooter being able to shoot stopped down at smaller apertures and getting good focusing results allows for faster shooting. For tripod shooters, there may not be much of an advantage. The more you know, the better your results. Shel > [Original Message] > From: Paul Stenquist > I sold my 105 some time ago. I could try it with a 90. But I would > never focus any lens at f8. What's the point? -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net

