Learning to freeview, Part I

[P3D <PTWW@xxxxxxx>]

Synopsis

A personal, antecdotal story about learning to freeview (FV) stereo pairs.
Primarily of interest to a) individuals who have not yet learned to FV;
b) individuals interested in helping others learn to FV.

Key Points

  2x2 stereo pairs can be an extremely useful aid to learning the specific
eye muscle control needed to FV.
  Nearsighted individuals should remove their glasses, at least during
the training phase.
  Lying on your back helps achieve the relaxation recommended for FVing.
  Awareness of eye dominance can be important in learning to FV.
  Sources for suitable supplies are suggested.

Full Text

Until recently my few attempts at freeviewing stereo pairs were all very
brief and wholly unsuccessful.  I had read the tips that occassionally
showed up on the list since I joined, and some instructions I had run
across various other places, but nothing seemed to help.  One day while
exploring 3D topics on the web, I came across Larry Berlin's tips for
learning to FV.  I followed the link for his offer of a FV starter kit,
and was disappointed when it said he had no such thing to send out.  He
*did* give instructions for how to build your own starter kit; when I
read them, they struck me as a brilliant approach.  (Great going, Larry!) 
See http://www.sonic.net/new/see3d.html

To briefly paraphrase, Larry's suggested approach is to create a stereo
pair on a transparency (by printing on a color printer at Kinko's); hold
a white piece of paper, with a large black dot in the center, at arms's
length behind the transparency, and focus on the transparency while
looking at the dot behind it.

A recent post of Larry's suggests he also has a file to download with a
suitable image pair to create the transparency.  I don't remember this
part, but I was browsing on a Mac in a library, and didn't have any
disks with me to format to get the process rolling anyway.  But reading
these tips did get some subconscious processor time slices working on
the problem, and eventually some FV thoughts started popping up. One of
these was that, being nearsighted, if I were to take off my glasses, I
ought to have a head start toward decoupling divergence and focus!  This
thought gave me the confidence boost needed to have another go at it,
especially with something like Larry's transparency tip. Learning to
"look through" a transparent object sounded a lot easier than learning
to look through an opaque piece of paper!

(Note: in a later search of the archives--didn't want to post something
that had been adequately covered before--I did find that some nearsighted
folks have mentioned they *cannot* FV with their glasses on.  So far I
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cannot either, but I don't have much FV experience yet, and haven't made
a concentrated effort to learn to FV with my glasses on.  Is there a
significantly near-sighted list member who *can* freeview while wearing
their corrective lenses?  That would give us motivation to keep at it!)

Another thought that popped up was why not use some of my 2x2 shoot and
shift stereo pairs to learn to FV?  I keep them in frosted back slide
storage pages, which have enough translucence to look through them, but
not so much transparency as to make the objects behind too distracting.
I realized I could hold the page up, and if I could hold my focus on the
slide pairs while looking through them at the table lamp in the distance,
I should be able to "get it."  With our current furniture arrangement, I
seemed to have three choices: 1) try to FV while standing up near the lamp;
2) move several pieces of furniture around so I could sit down while trying
to FV; or 3) lie on the floor and try to Fv.  Being lazy, I chose 3.  My
later search of the archives found a member's post expalining that he
learned to FV lying in bed at the end of the day.  He speculated his eyes
relaxed more readily because he was tired.  IMO, the eyes relax more
readily lying down, whatever time of day it might be or however tired or
energetic you are feeling.

During the first few attempts I could see the two images creep closer to
each other, but did not get them to fuse.  Every minute or so I would
halt the current attempt, rest for a moment, and start again.  Each time
the images seemed to get closer and closer, and eventually some elements
seemed to be overlapping...but I was not yet seeing 3D.  Very suddenly
without warning...there it is! Depth!  And a very relaxed, natural feeling
about looking at the scene!  Way cool!

One curiousity I was not anticipating based on reading other descriptions
of the FV experience:  I had a definite sensation of seeing *three* images
while FVing:  the 3D view in the center, and the two flat slides off to
either side at the same time.  Is this what other people experience also?

to be continued...



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