Archived posting to the Leica Users Group, 2003/04/26
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]I stand corrected. ;-) - -----Original Message----- From: owner-leica-users@mejac.palo-alto.ca.us [mailto:owner-leica-users@mejac.palo-alto.ca.us] On Behalf Of Johnny Deadman Sent: Saturday, April 26, 2003 11:59 AM To: leica-users@mejac.palo-alto.ca.us Subject: Re: [Leica] Digital Aesthetic On Saturday, April 26, 2003, at 11:38 AM, bdcolen wrote: > They probably will - but they may well come up with a firmware, or > software fix, and neither of those will require a new camera purchase. I don't think so. The chromatic aberration (CA) 'problem' is chiefly a lens problem, and (just possibly) a sensor issue, or more precisely an interaction between lens and sensor design. It is vastly unlikely to be solved in software or firmware. The only way to correct CA in software is to apply differential radial transforms according to the wavelength of light. There are ways of doing this but they are complicated and non-optimal. For example, one can apply different radial transforms to the R, G, and B layers (panotools will do this) but there is no way in hell they are going to do that in the 1Ds firmware and in any case theoretically it is the wrong way to do it and will cause softness in the edges. Moreover you would need to parametrize the transform differently according to which lens was being used and what focal length it was zoomed to. In any case, I believe the CA problem is chiefly a lens issue. Wide zooms are notoriously hard to correct for CA, and most 35mm shooters would not have seen the CA because most 35mm film simply isn't good enough to see the fringing. The 1Ds sensor, as anyone who's used one knows, is massively unforgiving of lenses. It will take all the lens you can throw at it and then some. Right now with the 1Ds we have reached the point where the lenses not the sensor are the limiting factor. > - -- John Brownlow pictures: http://www.pinkheadedbug.com warblog: http://www.unintended-consequences.com - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html