On Oct 16, 2007, at 11:56 AM, Steve Desjardins wrote: > While I'm think of it, does anyone have one of these? I seem to > remember that is created some metering problems, but I'm not sure > where > I heard this. > > http://www.katzeyeoptics.com/item--Katz-Eye-Focusing-Screen-for-the- > Pentax-K10D--prod_K10D.html
I have a customized Katz Eye screen for the *ist DS ... no focusing aid, my own custom pattern of lines and crop markings. Loved it on the *ist DS so I tried it out in the K10D. Unfortunately, it produced consistent underexposure of about -0.7EV in the K10D where the standard screen has proven to be almost exactly accurate all the time, so I put the standard K10D screen back. When I talked with Rebecca Katz about it, she mentioned that the K10D's standard screen is tuned differently from the *ist DS screen, to direct more light at the ocular. That means the metering sensors are calibrated to a different curve based on the characteristics of the standard screen. I don't know how well the ones they sell for the K10D work by comparison. Those who I've heard getting them for any of the Pentaxes with the split image rangefinder focusing aids occasionally say that the spot metering patter readings are off with some lenses. This is because the metering sensor is not exactly aligned with the optical center of the focusing aids, and how that pair of prisms behaves with a given lens and the metering sensor is not consistent as a result. But most people who use focusing aids like these screens anyway. I find the K10D's standard screen works very well for me. When it doesn't, I do a digital preview with the JPEG settings at default and use magnification to check critical focus. Godfrey -- 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.
