Hi John,
Have you done any spot meter comparisons between split prism screen
and matte screen?
I think this is the major issue, as spot sensor overlaps the split
prism. Prism transparency differs visibly from the matte area and
should affect the sensor reading - as this is calibrated for the
latter.
BTW, autofocus variations are not linked to the screen. I
experience too AF inconsistencies with MZ-5n and FA 50/1.4.
Servus, Alin
John wrote:
JAH> So far I've noticed no problems with the new screen. Pre- and
JAH> Post-screen install tests of the meter don't show any differences print
JAH> films are coming back w/o any problems. I haven't had a chance to run a
JAH> roll of slide film through it. Hopefully I'll get a chance to do that
JAH> this weekend.
JAH> Curiously the screen is demonstrating an interesting quirk in the AF
JAH> system...
JAH> If the lens Autofocuses from infinity to target, it's dead on. If the
JAH> lens autofocus from closup to target, it undershoots focus by just a
JAH> hair. The error isn't huge and I've determined that it's somewhere
JAH> between f1.7 and f2.0 on my 50mm/f1.4 lens (this by pressing the DOF
JAH> preview button on the camera.) It doesn't happen all the time, and
JAH> seems to be a bit more frequent on targets w/o very distinct vertical
JAH> lines. Heh... With the f1.4 on there it could be me moving the camera
JAH> ever so slightly fore and aft! =)
JAH> I'll spend some time with the cam on a tripod soon and see if I can't
JAH> tie this down a bit more.
JAH> Very interesting.
JAH> Oh... By the way... The screen works FANTASTIC with my MF lenses... The
JAH> whole reason for this endeavour as it is! :P
JAH> The split-image doesn't go dark until around f6.7 on my big Sigma 75-200
JAH> f2/8~3.5 lens. The matte screen area really lets things snap into focus
JAH> there too.
JAH> Overall, I'd say it's been a great < $10US experiment.
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