Beyond infinity ...

[Andrew Davidhazy <ANDPPH@xxxxxxxxxxxxxxxxxx>]

Many years ago, when I first started tinkering with strip, 360+ degree
panoramic cameras, in order to try to wake up the audiences as to the
possibilities opened up by the scanning camera I used to make this
observation:
                                                                   
"... if you take the axis of rotation of a panoramic camera and think
about projection onto a cylinder of the surface of a sphere located inside
the cylinder and tangent to the cylinder at the equator and its polar axes
coincident with that of the cylinder, then the location in space that the
N and S poles will touch the surface of the cylinder could be defined as
infinitely distant.
                 
If that is the case (if you buy into this premise!) then in any case that
a panoramic camera includes points beyond the axis of rotation of the
camera it reproduces subjects that one could define as being beyond
infinity. It will be interesting to note that those subjects will be
upside down with respect to the same subjects on "this" side of infinity,
they will be reversed left to right and also will be 180 degrees out of
phase with their counterparts." etc. (or something like this anyway!)

This was followed a set of slides that showed that when a panoramic camera
is rotated about a vertical axis but its angle of view is raised (such as
when a camera might be tilted upwards to take in the top of a building for
which the un-tilted camera has an unsuitable angle of view) the sides of
the building will not converge.

Later on this led to the realization that the "Goldbeck wedge" did not
allow sharp images to be made from one edge of the film to the other. But
that is another story.
         
Although I had photographic examples of both of these "effects" done in
late 1960's with traditional film strip cameras, today I made yet another
photograph in my lab with my simple, improvised, hand-scanner turned
digital-panoramic-camera and the effect is clearly seen. 
            
Because of the fact that the scanning is done with a linear array and the
pixels are much smaller than any slit could be, the sharpness of the image
extends very close to the "north pole" although eventually the effect of a
point turning into a line (where infinite distrotion is present) can be
clearly seen.       

In case you might be interested in seeing this image I've installed it at:

        http://www.rit.edu/~andpph/text-inifinty-pan.html

cheerio,

Andy  o o  0 0 o . o  Davidhazy, Imaging and Photo Tech
       \/\/\/\/\/\/          http://www.rit.edu/~andpph
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