Just to clarify... Each of the zooms I tested correctly maintains focus as it is zoomed. If you zoom in, focus, then zoom out wide and take the photo, the photo is sharp as can be. If you autofocus while zoomed out, the autofocus moves the focusing collar and the photo is then back focused. The optics are fine, the auto focus sensor or software are what cannot handle the wide angle.
Manually focusing is correct each time, so it isn't the focus screen, either. The fact that I have a habit of zooming in to focus them out to take the photo, plus the fact that the focusing screen is accurate, both mean that this has not been a problem until I finally got a wide prime. With the 21 Limited, the auto focus is never sharp at any distance. Perhaps the tiniest tweak of the adjusting screws will correct the wide angle back focus while not doing much to the tele focus. Perhaps not, which is why I was asking. By the way, this particular 21 Limited is in fact a bit sharper than the our 16-45. Brian -- Brian Dunn Photographic http://www.bdphotographic.com -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
