Thanks to everybody who responded to my question! It helps to know that my lens is not defective.
I was worrying because the manual for the D-FA 100/2.8 does not do a good job describing it: http://www.pentaximaging.com/files/manual/D%20FA_Lenses_112205.pdf "The Clamp switch locks the manual focus position...." "Focus manually, then set the Clamp switch to ON. The point of focus will be locked. Autofocus will also be disabled." * Do not turn the focusing ring forcibly while setting the Clamp switch to ON because there is a slight possibility that the point of focus may change" Well... "slight possibility" is "slightly" exaugurated, even for not very "forcible" turning. Igor -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
