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[MF3D.FORUM:792] Re: I need a MF 3D Dr.
- From: Paul Talbot <ptww@xxxxxxxxx>
- Subject: [MF3D.FORUM:792] Re: I need a MF 3D Dr.
- Date: Mon, 19 Jun 2000 16:55:27 -0500
Paul Talbot wrote:
> So in the worst of [bill's] examples, he'll have .454 inches
> (11.5mm) of non-overlap image area on each film chip. Taking
> 11.5mm from 70mm leaves him 58.5mm to work with. That is plenty
> for good mounting in the RMM mounts...provided he makes sure
> he uses a "center crop."...
>
> So I think that with Bill's wide film format and the data he
> came up with, he is probably avoiding close-up misery--at least
> for now.
I was hasty in deciding to post this in the "close-up misery"
thread. I had wanted to check the above numbers anyway, but
they don't directly relate to close-up misery. I had a feeling
at the time I should have checked Ferwerda first. (Eventually I
did, but still I didn't get it.) Now after some discussion off-
list, I understand the problem better. Drawing on an example I
was given, let's say the closest object in a scene is a coin
standing on edge, thin edge toward the camera. Say the physical
depth in the scene is not very great, and the scene is fairly
close. The MAOFD formula may yield a stereo base that is
significantly larger than 1/30 the distance to the near object.
It is possible that the left camera will see the "heads" side of
the coin, while the right camera sees the "tails" side. When
you go to view the two images in 3D, there will be problems,
even though the MAOFD has not been exceeded!
Extending the example to more likely real situations, it is
easy to see that if the base is so large as to see different
sides of a near object, fusing the two chips into a pleasing
3D image could be quite difficult or impossible.
I wonder if John B. could give us a formula to tell us when
this situation is likely to be a problem! ;-)
So I retract my statement and now have to concede I don't
know whether or not Bill ran into close-up misery in his
test shots.
Can't wait until some of us get a chance to see those bad
boys of Bill's! ;-)
Paul Talbot
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