P3D Re: Stereo Window Demonstration

["David W. Kesner" <drdave@xxxxxxxxxx>]

In p3d digest 3741 Bob Aldridge writes:

Before I comment on the following let me say that I have the utmost 
respect for Bob. He is far more knowledgable now that I could ever 
hope to be when it comes to stereo projection (and probably a 
whole lot more).

> And, Dr Dave, _you_ have missed the point of moving the
> window off the screen!

No I understand why it is done, I just believe there is a better way.

> The projectionist has absolutely _no_ control over the positioning
> of the scene relative to the window. The best he can do is avoid
> audience headaches by minimising the eye-gymnastics that bad
> mounting can cause...

It is that last sentence that says it all "bad mounting". It is my opinion
that a properly mounted image will have the proper separation (or
on-film-deviation) so that it can be projected with the window at the
screen and the proper 2.5" separation. That is of course you are  talking about normal projection sizes and not the 10 or 20 foot wide  screens.

Yes, there are images where this is not possible: an image with an 
object at 12 inches and infinity. No amount of manipulation of the 
chips in the mount or by the projectionist will make this a viewable  image (or at least without servere eye strain). You have to be aware  of what is in your image when you are shooting it.

What I am trying to propose or get across is that everyone should 
be forced to mount thier images properly and precisely so the 
projectionist doesn't have to do anything more than focus the 
image. I realize that this is probably a pipe dream and people will 
have to be continually adjusting their projectors, but I can hope!

That's all for now,

David W. Kesner
Boise, Idaho, USA

That's all for now,

David W. Kesner
Boise, Idaho, USA
drdave@xxxxxxxxxx