Olympus-OM
[Top] [All Lists]

Re: [OM] Poll on Focusing Screens

Subject: Re: [OM] Poll on Focusing Screens
From: "Daan Kalmeijer" <daan@xxxxxxxxxxxxx>
Date: Wed, 3 Oct 2001 22:30:46 +0200
That was excactly what I thought when I wrote this. I wasn't feeling like
ASCI art ... (and attachments won't work in here)

Draw a situation where a point is dead in the middle of your sharply
focussed image and light entering from a lens in front of it. Draw that same
point when in front of and behind the focus screen. You'll see that the
point gets shifted with the split screen.

Hmmm. This sounds just as fuzzy as my first explanation. :-)

Daan

Pictures of Insects at:
http://www.kalmeijer.net

> > If an image
> > is in focus then all light coming from a single point on the source of
> that
> > image must come together on one single point on the focusing screen even
> > when they travel different paths through the lens (f.i. one ray through
> the
> > left part of a lens and an other through the right part). A split image
is
> a
> > small prism where the top part looks at those rays coming from the left
> and
> > the bottom part looks only at parts coming from the right (or the other
> way
> > round). If an image is off focus then these two images come together
just
> > behind or in front of the focus screen. In that case the two half images
> > show a slightly different view and thus do not allign.
>
>  Okay, I think I see what you're getting at, but I definitely need to draw
> something on paper to make sure I understand.. Now I've got something to
> start with, though, which is a big improvement over where I was before.
>
>  thanks!
>
>  -- dan
>
> < This message was delivered via the Olympus Mailing List >
> < For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
> < Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
>
>



< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >


<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz