common tradeoffs to achieve lower price are more distortion, lower build quality, more vignetting, more corner softness, lower quality control, etc etc, there are lots of ways to make a lens cheaper...Thats why I kinda have a fondness for the old days, when there was OEM, all as good as possible and third party, all cheaper and not as good. At least you knew what you were getting. Now you have pro level third parties all mixed in with consumer OEMs and the brand name doesnt mean as much.
JC O'Connell [email protected] -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Joseph Tainter Sent: Tuesday, February 17, 2009 10:48 PM To: [email protected] Subject: Re: sigma 18-50 f2.8 Some Sigma lenses are quite good. When I've compared them against Pentax equivalents, though, the Pentax ones have proven better. One systematic problem is that Sigma lenses often seem to have more edge weakness than I like. I suspect that this is part of the design compromise that must be made to achieve a lower price. Joe -- 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. -- 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.
