Also, just like the improvements in the original SMC coatings were measurable in all lenses with them, the improvements were not VISIBLE in all lenses that had them implemented. Measureable difference is not always a visible difference.
JC O'Connell [email protected] -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Graydon Sent: Thursday, April 16, 2009 11:15 AM To: Pentax-Discuss Mail List Subject: Re: DA55* 55/1.4 follow-up On Thu, Apr 16, 2009 at 10:55:13AM -0400, JC OConnell scripsit: > Are you trying to imply that Pentax and other major brand multicoated > lenses have not been "wideband" color neutral across the entire > VISIBLE spectrum until these DA coatings came along? That seems > unlikely to me. [what is with the hundreds of blank lines at the end of your posts?] I'm not implying that; I'm stating that. NO coating, even the very best current coatings, is completely flat in its colour transmission characteristics; there tends to be a shallow dip toward the red and blue ends of the spectrum. Prior to current-generation (or possibly current generation minus one by now) coatings, there tended to be a fairly sharp dip in the violet, too. Any coating is going to involve a pile of tradeoffs in how it does colour transmission; more red means less something else, and so on. -- Graydon -- 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.
