Hello Roman, On Fri, 06 Jun 2008 10:09:01 +0300, Roman Melihhov wrote:
Note: I have only been using for for about two weeks :-) >How catz eye focusing screen works with apertures slower than 4 - 5.6? Fairly well, but be aware that there are a few variations: - regular ones - OptiBright enhanced ones - split-prism PLUS ones The one I have has an PLUS enhanced split-prism and it also has the microprism ring (but no line markings at all to keep it clean :-) You'll have to read up on their website about the exact differences. What I understood is that the PLUS treatment is for the split-prism only, and helps to make that usable with small appertures. I just did some tests, and allthough you need quite careful positioning of the eye, it still works at F/16 (with a 200mm lens) The microprisms still work sort-of, but I find them MUCH less usable than the split-prism. So when any straight lines are in the image I tend to use that :-) > From my earlier experience with non-pentax bodies and AF-screen with >microprisms it's not so good on apertures 5.6 and slower. In fact - it >may be useless or disturbing and given that some good DA series lenses I >own are f/4.0 or f4.0-6.3, I'd rather hear your practical opinion before >I decide to change my installed K20D AF-screen for katz eye. I have the DA* lenses mounted most of the time, so that will be F/4 or better, but just tested with an old FA 28-200mm Pentax, which is F/5.6 at the long end. That also works just fine, even when forced down to F/16 with the DOF preview. I agree with Bill Rob that in ANY case it is an improvement over the standard screen. I used it last week with the A* 200mm macro and combined with the superb manual focussing with that lens, the split-prism is an absolute joy to use ... Note: I hardly ever use spot-metering, which is the one area a split-prism may bite you by influencing the metering system ... Regards, JvW ------------------------------------------------------------------ Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
