Tool released an album with a bunch of stereo optic album art back in 2005 or so, with built-in glasses to go with them. I was home, sick, with time to spare, and tried to make these work. People online said they could see the images in 3D immediately, but it would take me 5-10 minutes of staring to make each page pop with depth. After I put the album down, I looked around, and - holy shit - the room around me was in 3D, like the stereo optic photos and art.
The effect faded after a few minutes. That's when it occurred to me that I'm some kind of stereoblind. I have depth perception, but it's almost like my brain uses an inefficient algorithm. The only time I naturally see depth that pops like that is when I'm looking out at vast, vast spaces - driving around the American southwest, for example.
I'm the only one in my immediate family who doesn't need glasses. My vision is sharp, it's good at night, and I often joked about how the 80s/90s idea that TV ruins your eye sight was a myth.
I think the joke is on me. Because I didn't spend enough time focusing on far away things, I never learned to relax my eyes that way, and Magic Eye never really worked for me. I like to think that explains why I sucked at sportsball (although did okay with soccer)
Back to when that Tool album came out - weeks later, I heard a story on NPR about a doctor who was challenging the accepted theory that if you don't develop depth perception by age 8, the synaptic paths are set, and you can never develop depth perception. By setting up a string, with beads placed a couple of inches apart, attach it to the wall, and then every morning, and stare at each bead... And people were able to learn depth perception!
I didn't ever set that up. Sometimes, through an old mirror, I can see depth. It's wild. But, for no good reason, I can't be bothered to practice on a string of beads, or whatever.
Don't spend too much time in front of screens, boys and girls. Go outside and play.