On May 23, 2012, at 5:48 PM, James King wrote: > 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…
Also possibly better at vibration dampening than metal mounts. -- Larry Colen [email protected] sent from i4est -- 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.
