Im talking about color transmission too. Well whatever your trying to say here, I just think it should be clear that you dont need the "new and improved DA SMC multicoatings" to get accurate visible color response across the whole visible spectrum in a multicoated lens. Its been achieved prior to DA lenses.
If you are getting TOO MUCH blues and violets relative to reds and greens with these new coatings ( Im not saying you are ) then they wouldnt be "improved" would they? JC O'Connell hifis...@gate.net -----Original Message----- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Graydon Sent: Thursday, April 16, 2009 5:09 PM To: Pentax-Discuss Mail List Subject: Re: DA55* 55/1.4 follow-up On Thu, Apr 16, 2009 at 02:53:34PM -0400, JC OConnell scripsit: > But your implying that DA coatings are better because the color > correction is better, I dont agree with that statement as necessarily > being true. I'm not talking about colour *correction*; I'm talking about colour *transmission*. The blue-indigo-violet end of the spectrum is obviously the hard part, or it wouldn't be _purple_ fringing, after all. I've never seen a transmission diagram for a Pentax camera lens; those I have seen (for high end sport optics) suggest that getting the 'only about 80% of the far violets make it through' dip out of the transmission is a recent (last five years) technological change. > Just because you have a DA lens with whatever coating you feel has > better color correction than another lens you have, doesnt mean that > the DA coatings are responsible or that DA coatings have improved > color correction or that color corrected lenses have not been availble > before these DA coatings. Color correction has been something that has > been attacked and addressed since color film was invented, only > "improved coating on DA lenses" is not fixing what would be a major > problem which is what visibly poor color correction would be... Ah, but this is not what I'm trying to talk about; what I'm trying to talk about when I say "the DA coatings are better" is that it looks to me as though more of the far violet light is getting through the lens at all, *not* "accurate far violet light is making it to the sensor". In another month, I could go find some of the flowers in question and post some photos; can't do that yet, none of it is in bloom. -- Graydon -- 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.
