Re: [photo-3d] re: hyperstereo images

["Dr. George A. Themelis" <drt-3d@xxxxxxx>]

At 05:52 PM 1/13/01 -0600, you wrote:
>Those are some pretty neat shots, Dave!  I like the clouds especially.  One
>problem I notice with some hypers is they sort of trivialize the
>subject....the mountain looks like some kid's sand pile to me. :)

This is a well-known effect of hyperstereos.  Increasing
the stereo base makes the objects within the scene appear
smaller.

One way to think of this is to imagine that YOU (the
observer) has become a giant with eyes spaced several
miles apart (the location of the two recording points).
If you don't like to transform to a giant then the scene
transforms to a small-scale model.  These are two
equivalent ways of explaining the end-perceived result.

The opposite effect is also very interesting.  Reducing
the stereo base makes the objects appear larger. Some
time ago I took a picture of small passage-way, only
2-3 feet wide.  I used a smaller stereo base and, in
the absence of other clues, this passage-way looks like 
an enormous bridge (I remember I entered it in Detroit
when the subject was "bridges").

George Themelis