I'm not sure about the 18-250, but using some of my older K and A lenses probably causes some air circulation simply by focusing. Heck a modern unit focusing lens like the FA 43mm Limited does it too.
Igor Roshchin wrote: > Can a zoom lens be used as a vacuum cleaner? > (cleaning the space around, and collecting all that dust on the sensor) > > A fellow on dpreview forums claims that operating zoom on Pentax > 18-250 provides suction that leads to dust penetrating inside the lens. > > http://forums.dpreview.com/forums/read.asp?forum=1036&message=27304333 > > Any comments? > > Has anybody seen any objective results about this suction effect in > zooms? (Most zooms do not have dust-sealed design, so this effect should > not be limited just to this lens.) > > Igor > > -- Vote for Cthulhu. Why settle for a lesser evil... -- Dr. Jerry Pournelle -- 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.
