The matte/prism side should be near the pentamirror/pentaprism,
not the mirror. It makes sense because that is a defined plane in the
camera.... the screen can be anything, so long as it's flat against that
surface.
That's what I said, didn't I?
Yes. I had just read all the posts regarding the subject and
wasn't really answering your specifically... just general clarification.
So, you'd likely
not be able to change the thickness *too* much. I'd bet it works out that
it'd have to be significantly thicker to screw it up too much.
Depends on definition of significance. SMC has significant effect but is ~1/4
wavelength thick....
I'd say SMC is on a whole other scale. The screen is thick enough
to be a "bulk transmission media." The question is whether a screen
that's 0.050" vs. 0.040" would make a noticable different in the resulting
focal point. The fraction of that distance to the transmission path to
the lens is pretty small. At least that'd be my engineering guess, but I
know little of optics... :)
Just as a note. I'm pretty sure that when I first installed mine
I didn't quite have it in there right. When I actually took a few test
shots at an oblique angle, the screen-focus was slightly different than
the picture taken. I took the screen out, rotated 180 degrees (did NOT
flip it over. It wasn't *that far out), and more carefully put it back
in. Here's the result when focusing on the line between the 9 and 10
towards the middle of the chart.
I would think installation needs to be as perfect as the system allows to make
it work properly.
It just seemed odd that I could screw it up. With the way the
screen holder pivots in place, it seems like it should either be correct,
or not. If not, the holder wouldn't close.
-Cory
--
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* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
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