Anthony Farr escribió: > The difference between IR focus and visible wavelength focus is not constant > from lens to lens. Different designs of the same focal length can have > different IR focus corrections, and the correction is not necessarily > proportional when comparing lenses of different focal lengths. > > UV transmission in any significant degree requires exotic glass so isn't > normally a consideration. > > I know nothing about the spectral characteristics of Pentax's AF sensors; > perhaps you have guessed that IR contamination is the cause of the problem. > It sounds feasible. >
AFAIK, the AF sensors in Pentax SLRs (and other brands too) have a built-in IR filter. It is clearly shown in the AF sensor schematics in Bojidar Dimitrov's K mount page: http://www.bdimitrov.de/kmp/technology/AF/index.html (that is the SAFOX IV sensor). Carlos -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
