I received a 21 Limited. Center only autofocus always greatly back focuses on both ist-DS cameras, more on one than on the other. The 45 degree focus chart showed the 21 Limited back focusing almost off the far end of the paper.
I tested other lenses and found that they all back focus when set to wide angles. The amount seems to be proportional to the angle. For example, you could set a 16-45 on a tripod, aim at something 7 feet away, zoom in to 45mm, focus, then zoom out and focus again. The more you zoom out, the more the autofocus changes. All this time I have been zooming in, focusing, zooming out, then taking the picture. It works fine until you get a wide prime like the 21 where there is nothing to zoom. When aimed at something across the street it tries to focus past infinity and hits the stops. Research on the Internet finds discussion about adjusting three screws under the base plate of the DS. These hold the auto focus sensors and you can adjust for front or back focus. So I'm wondering if anyone here would care to take a 16-45 or 18-55 or the like, zoom in and aim at something across the room, see on the focus scale what distance it chose, then zoom wide and focus again to see if it changed. Do all Pentax digital cameras back focus at wide angle? Has anyone here tried the adjustments under the base plate? Has anyone had a Pentax repair center successfully fix this issue? Brian -- Brian Dunn Photographic http://www.bdphotographic.com -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
