T3D Re: Cardboarding

[PK6811S@xxxxxxxxxxxxxx]

Usually I see two worlds: W1 with the left eye and W2 with the right.  They
are usually not very different, but the differences allow my brain
to establish relative depth.  It seems in Bill's experiment he is 
trying to reduce the differences between W1 and W2 to zero (matte,
featureless sphere with no background) and find out whether his brain
can find any depth.  I'm guessing that if I was presented with such
a stereo pair without advance warning I would not be able to find any
depth - could not tell whether the surface was concave, convex, or flat.

Now draw a little stick figure on the surface and - voila! depth suddenly
appears from nowhere, or rather from the introduced differences between
W1 and W2.

Bill, are you effectively reducing the differences to zero?  Or are
you allowing some differences to remain, and what would they be?

Paul Kline
pk6811s@xxxxxxxxxxxxxx


------------------------------