This instructable is about an optical illusion I've discovered, and it's pretty realistic when done correctly! I've come to call it, "an image of one's former self." because that's exactly what the illusion is. Although it's quite possibly the coolest illusion i've ever seen, it's not something that everyone can do due to the materials involved, and some possible health problems.
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Step 1: DISCLAIMER AND HEALTH AND SAFETY
This optical illusion involves intensely bright flashes of light,dark areas, and a fair amount of disorientation! I urge whoever tries this to be careful as the light will literally, cause temporary blindness. Try to move as little as possible during this duration, and make sure you have an object you can firmly anchor yourself to. This experiment isn't reccomended for those who have a history of epilepsy either for obvious reasons. also, make sure that the light is NOT pointed directly at your face, as the light can cause damage to the cornea.
as always I'm not responsible for anything that happens to you or your possesions, should you choose to try this experiment.
Step 2: Materials
the materials are fairly simple.
1. a dark room, with a mirror. (preferibly on the wall. doesn't have to be light tight. you should be able to just barely see. I found my bathroom to be perfect)
2. your eyes.
3. A powerful photographic flash. Note: a tiny little camera flash isn't going to work. I had to use one of my mom's professional camera-mount flashes to get this to work, and even then, it had to be set to the highest power level for it to be bright enough. you can try it with a regular flash, but if you want real results, you'll need a professional grade flash.
Step 3: The Experiment
Take all of the materials into the room you want to try it in. turn off the lights and let your eyes acclimate to the darkness. you should be able to just make out your hand. once you're acclimated, hold the flash at your waist and point it up at the mirror at a 45 degree angle.
make sure the flash is fully charged, and then set the flash off! STAY MOTIONLESS! because your eyes are acclimated to the darkness, and they just received an intense amount of light in such a short time, you'll literally loose your sight temporarily. about 1 second after setting the flash off, turn you body 90 degrees left or right of the mirror, and then stare into space...
Step 4: The Result
If you've done it correctly, you should see the picture you saw in the mirror of yourself when you set the flash off...but if you reach forward...you can't see your hand!
my guess is that, when you set the flash off, you see yourself in the mirror for a fraction of a second, and then you go blind, as your eyes try to re-acclimate. when you turn, because your eyes aren't acclimated, your brain defaults to the image you saw in the mirror because of the property our eyes have called persistance of vision.