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Old 03-22-2006, 12:49 AM   #29
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Join Date: Feb 2006
Location: Stuck in the Matrix somewhere in Santa Clara CA
Posts: 10,783

Originally Posted by forehander
Interesting. I'm due for a checkup for my contact lenses. If I remember, I'll try to ask my Optometrist. He does the dominant eye test on his patients.
I'd be interested in hearing what he has to say abt eye dominance percentages. Is he a behavioral optometrist by any chance (... more specifically, does he provide sports vision training)?

I'm also wondering if an individual can change their eye dominance thru training. I got hit in my dominant eye with a ball more than 8 yrs ago. The retina became partially detached &, as result, I still see an occasional phantom light flash when I turn my head quickly. However, the real problem is that the near vision in my dominant eye has deteriorated considerably & I'm wondering if it is worthwhile to try to get my brain to accept the image from my other eye as the dominant view.

Originally Posted by C_Urala
I have always had difficulties in trying to make this test. When I make the circle and try to look through it with both eyes, I either can see the distant object and see the circle in duplicate, or I can see the circle and see the object became doubled.

Do I do something wrong? or it's my eyes that are wrong?
This is actually quite normal. It is a matter of convergence. Most of the time our eyes both focus and converge at the same distance. If we look at an object in the distance, our eyes will probably converge for that distant object. Objects that are much closer than that distant object may appear as an unfocused "double" image. On the other hand, if we close-converge, then objects in the distance may appear double.

Try this experiment: Hold up the index finger of one hand about 9" in front of your nose. Line up your other index finger directly behind it abt 2 feet from your nose. If you focus/converge on the closer finger, the one in the background should appear double. If you focus/converge on the distant finger then the finger in the foreground will appear double.

With the eye dominance test that we've suggested in previous posts, try adjusting your eyes to change your focus/convergence to minimize the double image problem. Your other option is either to change the size of your viewing window or change the distance of your window from your eyes to try to minimize the double image effect.

Sidebar-- Thru training, we can learn to focus and converge our eyes independently quite well. We can learn to focus at something near while are eyes converge off in the distance (aka divergence). Or, we can close-converge while we focus on some distant object.

Sometimes we already do these things unconciously, either when we cross our eyes or when we are staring off into space.

Remember those 3-D Magic Eye stereogram pictures that were popluar in the '90s? In order to see the 3-D images hidden within the pictures, you had to adjust your eyes in the proper manner. The trick was to get your eyes to focus and converge at different distances. Usually, your eyes would focus right at the surface of the picture. With your eyes still focused at that distance, you needed to get your eyes to converge at a different distance.

Most, but not all, of these types of 3-D pictures had you converging your eyes past the picture. In this case, if (for example) you were standing 6 feet from the picture, your eyes would be focused at 6 feet, but might have to converge 12 feet away (6 feet past the picture) in order to see the hidden 3-D image.

Some other pictures were set up for close convergence instead. You would need to sort of cross your eyes to see these images. If we were standing 6 feet away, you would still focus at 6 feet but your eyes would converge at 3 feet instead.

Check out the following 3-D tennis stereogram (from Blue Mountain e-cards):

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