On 16 Nov 2004 at 1:51, Jens Bladt wrote: > The Sigma shot really has a lot of purple fringing. Mine doesn't have a lot, > just a little, hardly noticeable. Avoiding CA totally is not possible in the > real world, where light is ruled by the laws of the rainbow :-). Some computer > programs can even deal with this.
I agree there are ways to deal with CA to a point, for instance I "fixed" the Sigma shot that I referred to, the lens seemed to have a pretty linear CA curve and was pretty sharp to the edges, not all lenses are this linear particularly wide angle zoom lenses. > I believe my test serve me well. They tell me to do somthing about the > Tokina AT-X (probably a new bayonet and a CLA), which used to be superior to > the > other lenses in my small test - or replace it. They also tell me that the two > other lenses are not too bad, and can successfully be used at smaller > apertures > than F5.6. The lessons to be learned from the edges of the images do not > really > differ from those of the centre. Granted the tests worked for you, I assumed you shared them so that they may be useful to others. > I don't need sharp edges if the centre isn't > sharp. I am not an artists, doing photographs for exibitions or sale. I see where we differ, regardless of the use I'm more inclined to prefer lenses with a uniform look across the frame (apart from the A50/1.2). > I just do photographs for books and presentations. > No one, but me, will look at my photographs as such - only at the subjects > they show, perhaps the composition and colours. So, I don't need expensive > lenses, which i DK retails for what is similar to three weeks pay, before > tax. I'd rather use a Tokina, a Sigma or a Pentax consumer lens - and then > take 4 weeks leave! :-) Well we do see them occasionally :-) I've no problems with what anyone else purchases and I've no idea of your financial position, I was just commenting on the tests. A good holiday means a likelihood of many more great shots so they balance each other out ultimately. Cheers, 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
