Interesting! 5mp would be plenty enough for me. Besides,the more pixels, the longer the time in between shots...
rick ---- At 09:37 PM 8/8/2006, you wrote: >Some interesting comments I lifted from the ProRental list. > >Powell > >===================================================================== > >Date: Tue, 08 Aug 2006 02:36:26 -0400 >From: Steven Inglima <[EMAIL PROTECTED]> >Subject: [ProRental] Resolution and the limit >To: [EMAIL PROTECTED] > >In response to Lee: > ><All other things being equal - yes, larger pixel sites means more >volume of light captured and that means better signal to noise ratio and >greater dynamic range. Smaller pixel sites also affect the ability of a >given lens to resolve details to the resolution of a chip. > >All else being equal, of course, this is correct. What can change the >equation is the quantum efficiency of the sensor itself. If a given >sensor converts, let's say, 20% of the photons into electrons, and the >gathering area of the photo site is reduced by 20%, then should expect >to lose dynamic range as the shadows will be getting relatively little >information. But, if a different sensor can achieve a conversion of 40% >of the photons to electrons, then it's possible to shrink the photo site >and retain the same dynamic range. > >We are already at the limit of resolution with many of the lenses >currently available and more pixels crammed into the same size chip are >simply not going to offer much more that bigger file sizes! > > >There are rumors flying around about a 22mp Canon - even the very best >of the current Canon lenses would fail to perform at the resolution of >such a chip -- bigger file size but the same image detail and a good >chance that there would be lass dynamic range as well. Doesn't sound too >promising to me! More sophisticated noise reduction could help with the >dynamic range part of the equation but it would require much more >advanced optics to provide the needed extra resolution and I don't see >that happening any time soon, certainly with popular zooms! > > >Without confirming or denying the existence of an upcoming 20mp+ Canon, >the math of optical requirements is something that we can demonstrate. A >5 micron photosite would require 100 lpm resolution from the lens. While >this is indeed a high benchmark, there are a number of lenses that Canon >makes today that can achieve this. And of course, if a slightly larger >micron photo site, let's say 5.5 would be employed, that would lower the >resolution requirement. So, in other words, you can't necessarily know >what's about to happen performance wise in digital photography on the >immediate horizon :) > >1/ (2x .0055)= 90.9 lpm requirement. There are quite a few lenses in the >Canon system that can achieve this resolution. > >You can read about the Nyquist limit and other Fourier equations at : > >http://mathworld.wolfram.com/NyquistFrequency.html > >Or, you can just keep posted...cause Canon isn't likely to announce that >they will never make a camera with more resolution than the 1Ds mkII. > >Best wishes, > >Steven Inglima > >-- >PDML Pentax-Discuss Mail List >[email protected] >http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
