An A lens doesn't have any way of reporting the focal length - that's done over the digital signal pin, and only came in with the KAF mount.
The K20D has to have focal length input set manually. If it's the same as the K10D, though, it might not ask if you change lenses without turning the camera off and turning it on again with the A lens mounted (I occasionally make that mistake when I'm using the 1.7x AF adapter with my A* 300). On Sun, May 17, 2009 at 02:47:02PM -0700, Joseph McAllister wrote: > This might be why my K20 did not ask the focal length of my A* 300 ?4 > when attached to the AF 1.7x tc. It should have, but perhaps it DID get > something from the 300 as to focal length. Of course, the photos were > soft on tripod, so maybe I should have gone to the Custom Functions and > forced a 500mm reading. (There was camera movement, as the tripod was not > my sturdiest) > > On May 17, 2009, at 12:14 , Adam Maas wrote: > >> but also impractical to >> evaluate all F and later lenses (A and earlier lenses don't identify >> the model to the camera and therefore couldn't support the feature >> in-camera) > > Joseph McAllister > pentax...@mac.com > > http://gallery.me.com/jomac > http://web.me.com/jomac/show.me/Blog/Blog.html > > > > > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
