Subject: Hi-res random dot stereogram of fractal -AAK

From: [email-masked] (Andy Kinsman 253-7794)
Date: 17 Jun 92 15:16:25 GMT

Here is a random dot stereogram of a chunk of the mendlebrot fractal
set.  After viewing with far-eyed techniques, try cross-eyed.  You
may like the results better.

Next week a post of a human face, probably should find somebody better
looking than yours truly:-)    -AAK

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From: [email-masked] (Aubrey McIntosh)
Date: 20 Jun 92 21:46:31 GMT

In my informal survey, approximately 5 people could achieve stereo without
requiring artificial aids.  The field was about 30.  Surprisingly, the
chemists were poorly represented in the lot, and the department generally
thinks I'm daft.

Clearly, artists were the best represented, all three saw the image within
a minute of instruction.

So.  My friend and I devised the characteristics of a self-instructing image:

1)  An easily recognizable portion of the image, e.g. the tip of the nose,
should be so elevated in the image that the shift corresponds to 1 random
dot period.  e.g. they overlap, and you see an image on the paper without
special focusing.

2)  A more strongly attended object should be a short distance deeper in the
image.  Probably the most strongly attended object would be a pair of eyes.
Fortunately, they are typically deeper in the image :-)

3)  The other characteristics, which may cause ghost images in the flat
printing, should not be so strongly perceived.  Again, a face and perhaps other
background would satisfy this.

Aubrey McIntosh  /  Chemistry  /  University of Texas  /  Austin, TX 78712
...another Gaelic learner...