I would hazard a guess that most people who buy an SLR have one lens. Not guys like us, but everyone else. I wonder if there are stats on the number of lenses there are for every body sold.
Jeffery Sent from my iPad Jeffery L. Smith New Orleans, Louisiana USA On May 23, 2012, at 20:24, "J.C. O'Connell" <hifis...@gate.net> wrote: > pentax used "modern" plastic on some filter rings of their f series lenses. > those rings often crack and break off with age. Metal is better. > > ----------------- > J.C.O'Connell > hifis...@gate.net > ----------------- > > -----Original Message----- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of > James King > Sent: Wednesday, May 23, 2012 8:48 PM > To: pdml@pdml.net > Subject: Re: New DA50/1.8 Plastic Mount > > P. J. Alling wrote on Wed, 23 May 2012 09:20:38 -0700 > >> Lenses are a long term investment, at least they used to be, plastic on a > bearing surface implies the opposite. No matter what plasticizers are lost > over time and the material becomes brittle and subject to cracking. > Eventually something important will break. Heat will exacerbate this > process. If the lens was cheap enough to be disposablethat would be fine but > it's not really. > > It ain't neccesarily so! I'm confident that the Pentax plastic lens mount > is made of a modern engineering plastic; these are heat-resistant, often > self-lubricating, and do not contain volatile/migratory plasticizers. > Unless subjected to severe mechanical stress it's likely that they will > outlive the user. > > Regards, Jim > -- > 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. -- 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.
