Re: PePax and dollhouse effect

[P3D Larry Berlin <lberlin@xxxxxxxxx>]

Hi John,

It seems that part of the problem is that of aperture size. If you use a
long lens, which magnifies the scene but doesn't really get you closer to
it, the apparent flatness is due to the fact that a change in perspective
did not occur with the magnification. Wouldn't a corresponding increase in
aperture, along with the longer lens, correct the perspective problem and do
away with the dollhouse effect?

                        0                       object






                     |-|   |-|                   Standard  aperture






                 |--|         |--|              Longer lens and larger aperture


A longer lens w/increased aperture could subtend an equivalent perspective
angle of the object as that of the smaller aperture closer to the object.
This step combined with the magnified image would provide an equivalent
aspect of the image as the closer lens. Therefore, increasing the stereobase
to get an equivalent parallax, combined with the long lens and aperture
increase would indeed accomplish the goal of an orthagonal view, would it
not? Isn't there an existing formula for this that includes the aperture
size in the calculation? 

In other words, to really pretend to be the giant and have the giant's view,
you have to also imitate the giant's eye size, and not just the eye placement.



At 08:48 AM 9/9/96 PDT, you wrote:
>Did that make sense?
>John
>
>
Larry Berlin

Email: lberlin@xxxxxxxxx
http://www.sonic.net/~lberlin/


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