Did you play with only one eye open, or just one contact lens? I have worse vision than you (-8.0, -7.50), and I know that I can still function with just one lens in of needed. You definitely still have stereo vision even if one input is blurred. Your brain does quite a bit of compensation, and I can imagine if you operated this way for months that your brain would be even better at assimilating the noisy information from your "bad" eye.

Sulam is basically correct. I was born with strabismus (my eyes don't focus on the same point). To avoid perpetual double vision, my brain compensates by basically only using one eye at a time. It switches automatically when I'm looking to the side, and I can also switch consciously. (My color perception is very slightly different in each eye, it's weird.)

It turns out that stereovision is the least important of several depth cues humans use, and is only really effective out maybe 10 feet or so--beyond that the parallax is too small to give much useful info, and we rely on apparent size, relative motion, surrounding context, etc. I can catch a ball just fine, as an adult.

It's really only an issue within arm's reach, and then only when I'm distracted. Occasionally I'll reach for something without paying attention and miss by, like, a foot. Also, I can't use 3D glasses. (With the new polarized kind I can at least wear them and see a normal 2D movie. With the old red/blue kind, everything would be either red or blue, depending on which eye I was using.)

It isn’t just depth perception that is improved with binocular vision, there is binocular summation, which helps improve acuity. Two is better than one. However as you say, stereopsis seems to be one of the least important parts of sight.

You might have an advantage with not being able to watch some 3D movies - you can tell your friends/family that a medical condition prevents you going to them.

https://en.m.wikipedia.org/wiki/Stereopsis

https://en.m.wikipedia.org/wiki/Binocular_summation

> (My color perception is very slightly different in each eye, it's weird.)

I have comparatively uninteresting/normal vision (biggest issue shortsightedness) but I have this too. My left eye sees more blue, my right eye more red. Looks like the cone distribution wasn't perfect.

I'm not sure, but I think the sun's rays don't have much of a blue component: my left eye gets fractionally less sore from bright sunlight, so if it's really bright out I'll generally be closing my right eye.

The sun emits black body radiation with a 5800K temperature, which means its emissions peaks at yellow-greenish, but it still emits around 90% of blue compared to green

How about compared to red? That might suggest whether exikyut's experience (red-seeing eye more light-sensitive than blue-seeing eye) is coincidence or related.

I was trying to make the same point, I think? I was just trying to note that I have done the single contact lens thing as well, and even after just a few hours, your brain starts compensating for it.

I played with one contact, and if you have vision as bad as mine you know there is essentially no chance that I would be able to build a stereo image of the ball with one eye uncorrected. I know this because I had to relearn how to play, and I found myself using other cues for depth, like what the ball was occluding.

I crushed my glasses with my butt once, and went without for a year or so until I could get new ones.

Once I got the new glasses I was astonished at how flat and "PlayStation-like" everything looked. My depth perception was thrown off and everything looked much closer to me than it actually was.

I think my brain was using blurriness as an indicator of depth, in addition to binocular vision, and with my myopia corrected it lost that information and had to readjust to relying primarily on binocular vision to gauge depth.