Re: II vs. X (Parallel vs. Cross viewing)

[P3D Dr. George A. Themelis <fj834@xxxxxxxxxxxxxxxxxxxxx>]

Reply to message from andrew@xxxxxxxxxxxxxxxxxxxxx of Tue, 22 Apr

>Considering the value of dark vergence varies between individuals,
>I believe it is a misnomer to use the term "relaxed" when referring
>to the parallel view technique.  For some indeed it will be relaxing
>but for others it will be straining.

Considering that cross viewing usually requires that you cross your eyes
fairly close to your face (10 inches or closer?) while parallel viewing
requirs that you cross them at a couple of feet or further, I cannot see
how cross viewing can be more relaxed state for some people.  Do these
people cross their eyes at 5 inches when then "daydream"?  

Also, considering the link between convergence and accommodation, do these
people actually accomodate at these close distances, or have they broken
the link while daydreaming?

And what percentage of people actually fall in this category?  Seems to me
that the natural daydreaming relaxed state of the eyes is "defocused" and
"deconverged".

I do not doubt that for many people cross-viewing is easier to achieve than
parallel viewing, but I think that this is realated to muscle control and
not to what is more relaxed.

Keystone has a series of eye-testing cards that test these features, I
believe.  One card has an arrow in one image and a scale in the other.  As
you look with eyes relaxed, the arrow points to a certain number.  This
measures your "relaxed state convergence".

For the record, I can both II and X but find II more comfortable in the
long run.  While II I feel like meditating.  While X I feel like
excercising.  I can II view cards (3") but at some distance from my face.

-- George Themelis


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