In response to WordPress Photo Challenge: Curve
Many people think that, when someone with myopia wear glasses, his/her vision is the same with those who don’t need glasses. The fact is that, while glasses do make things clearer, it does come with many side effects. The higher the myopia, more thicker glasses required to make distance vision clear, and more side effects come with thicker glasses.
The well known side effect is minification. Minus glasses to correct myopia make things smaller, approximately 2% per diopter. That means, with my -12 glasses, I see things 25% smaller compared to normal eyes. Contact doesn’t minify things, which is why I prefer to use contacts than glasses.
The other effect of minus glasses is peripheral distortion. Photographer know this as barrel distortion, in which the edge of picture taken with camera appear curved. Vision behind minus lens also suffer from the same effect, where things in peripheral look curved. Compare the two picture below
The picture on the left is my vision without glasses. While everything look very blurred (try to locate the faucet), the door frame on the left is straight from top to bottom. When I put on my glasses, things got in focus (now can you find the faucet?). But, the door frame on the left look curved.
Thankfully, after decades of wearing glasses, the brain got used to the distortion, and simply cancel it out. I hardly notice the distortion, unless I really try to feel it.