Julian Loke wrote: > My reading of that web page > http://medfmt.8k.com/third/af.html > Indicates that a 2x eyepiece magnifier was used to view the focussing > screen ground glass.
That's indeed what the web page says, but I couldn't find such a reference in the cited Pop Photo article, which indicated a "small microscope," and later, a "supplemental eyepiece attachment" (don't hold me to the exact wording here ...). I suppose it's reasonable to assume the attachment was 2x. The article that I'd had in mind (and I haven't been able to find it) did use a low-power microscope on a film-plane groundglass. As I recall, it found discrepancies between film-plane and viewfinder focus just as with AF vs. film plane (I thing the MF using the focusing screen may have been slightly better than AF, but I'm not certain). There is no question that a magnifier helps. I often used the DW-21 6x magnifying finder with my F4, and found that achieving sharp focus with it was much easier than with the standard DP-20 finder--it's something I still kinda miss in the EOS system. There's a big difference between 6x and the 2x that you get with a clip-on magnifier--and you can see the entire image area. Nothing's ever free, though, and the DW-21 really only was usable on a tripod with fairly stationary subjects (and it was non-metering, so you only had the F4's behind-the-mirror spot meter). Was MF with the DW-21 better than the F4's AF? I felt it was slightly better, but I never really gave it a rigorous test. And the F4's AF was abysmal when compared with the EOS-1n. Even so, focusing with the 105 mm f/2.8 AF Micro-Nikkor wasn't nearly as easy as it was with its MF predecessor, because a small twist of the focusing ring caused a comparatively large change in focus--so any MF advantage was somewhat lessened. I converted to the AF lens because it offered AF when used as a medium telephoto, as well as 1:1 without an extension tube, but there were many times doing close-up work when I wished I'd kept the MF lens ... Jeff Conrad * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
