On 4 Jan 2005 at 10:55, John Whittingham wrote: > > it seems relative to the distance from the focal > > plane like a severe Longitudinal Chromatic Aberration (LCA). > > Would this not be evident on all telephoto lenses to some greater or lesser > degree?
Sure but lesser or non-evident is more desirable of course. ED elements have been employed in Pentax lenses in order to reduce LCA and TCA and in their long fixed FL lenses it seems to do a good job to pretty much negate visible CA. Looking back at Pauls shot again it's sharp and contrasty but the blue/yellow fringing around the twigs to the right is quite obvious (despite the relatively small image dimensions). Unless the image was a 1:1 crop of a high res scan I'd suggest it is excessive and I'd be a bit disappointed as it would have spoilt the shot for me. Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
