I think JCO is correct. Fringing doesn't seem to be related to CA. It has more to do with the way digital sensors deal with high contrast. However, some lenses seem to be more prone to it than others. In regard to what Mark Cassino said in an earlier post, my A4005.6 and A2X-S combination, which has to be shot wide open most of the time, produces purple fringing with both the K10D and the *istD in equal amounts. I just deal with it. Paul On Apr 14, 2007, at 12:59 PM, J. C. O'Connell wrote:
> I know what an APO lens is. If the problem, > which is FRINGING, not CA, is not caused by CA, > then getting an APO lens to minimize or > eliminate CA, isnt going help the FRINGING > problem at all. > jco > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of > Digital Image Studio > Sent: Saturday, April 14, 2007 12:46 PM > To: Pentax-Discuss Mail List > Subject: Re: Full frame lenses and the K10D, CA anyone? > > > On 15/04/07, J. C. O'Connell <[EMAIL PROTECTED]> wrote: >> FRINGING is not causeed by CA, so getting >> an APO lens to eliminate CA is not going >> to help the FRINGING problem. > > APO lenses are precisely designed to minimize longitudinal/axial > chromatic aberrations, such a lens may still exhibit some lateral > /transverse CA however this type of aberration is able to be remedied > during RAW conversion as previously mentioned earlier in the thread. > > > -- > Rob Studdert > HURSTVILLE AUSTRALIA > Tel +61-2-9554-4110 > UTC(GMT) +10 Hours > [EMAIL PROTECTED] > http://home.swiftdsl.com.au/~distudio//publications/ > Pentax user since 1986, PDMLer since 1998 > > -- > 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 -- PDML Pentax-Discuss Mail List [EMAIL PROTECTED] http://pdml.net/mailman/listinfo/pdml_pdml.net