Going to the movies has always been a favorite Friday night outing in my family. It seems nowadays every other new movie release also comes in a 3-D version. But what’s it all about? Is it worth the extra ticket price? Do the 3-D effects work for everyone? If not, why?
We live in a three-dimensional world with height, width and depth. Our brains make sense out of this partly due to the help of our binocular vision. Binocular vision means our visual system uses images from two eyes, simultaneously. Lower species that have their eyes on either side of their head don’t have binocular vision, but bilateral vision. Like snakes, horses and bunnies. But humans, along with many other animals, have eyes that sit at the front of our skull, side by side so we can see things straight ahead of us. Now, since our eyes are situated a few inches apart, they each point at a particular target from a slightly different angle. This is a good thing because these two images go back to the brain and combine to become a 3-D image. So the expression, “It takes two to tango” is true! We need two eyes, working together, to see the 3-D effects at these movies.
The special glasses they give you have a filtering property that’s different in each lens, mixing up the information you are looking at to send a more complex signal to your brain. This makes images on a 2-dimentional screen appear in depth. That’s why you think you can reach out and touch things as they seem to leap out at you. It’s really quite cool.
But it doesn’t work that way for everyone. Why? Because not everyone has two equally functioning eyes. Some people have a weak eye, called amblyopia. Or they have a cataract or other pathology in just one eye, making that eye see poorly or not at all. The cute 3-D glasses on these people won’t do a thing. Surprisingly, many people are not aware of their poor binocularity until they feel they’ve been ripped off at the theater. Thankfully, in our everyday life we don’t always notice these discrepancies because the better eye picks up the slack.
Not sure about your own depth perception? Have a complete eye exam to be sure your eyes are both healthy and that your glasses or contact lens prescriptions are ideal. Ask your eye doctor about your depth perception. A simple quick test can determine how well your eyes do at this. Then you and your doctor can see if anything can be done to fix it.
“Fixing it” may be as simple as updating your prescriptions or switching out your “near” contact lens for your “distance” lens when you go to the movies. Another remedy may be cataract surgery.
More often than not, however, there is nothing that can be done. Amblyopia, for example, usually sets in at birth or soon after. When caught early, ideally before the age of nine, depending on the cause, amblyopia may be corrected. But if you are an adult your options are much reduced.
After talking with your eye doctor about these issues, you can now understand a little better why that 3-D experience didn’t work for you.
There are also some people who see all of the cool stuff jumping off the screen at them but they get a head ache or they get nauseous or sleepy. If you are one of these folks, your “binocularity” is working, but not perfectly. Kind of like having one leg a little shorter than the other. For the most part it’s no big deal, you just get by. But your alignment is off a bit. The best advice for you folks is to not spend that extra cash for the 3-D experience.
But for those of you that love that popping out effect, go for it! It’s an exciting concept that gives most people an awesome, unique show! Luckily, regular 2-D movies are still out there for all of us to enjoy as well!