By now you hopefully know that more megapixels don’t necessarily make a better camera. For one thing, you can almost double the megapixels of a camera while only gaining about a 40% increase in resolution. For another thing, it takes a lot more than just sheer number of pixels to produce a decent image. Nevertheless, point-and-shoot cameras with ginormous megapixel stats (now topping 12 MP) continue to hit the market. But Ross at Petavoxel says there’s another reason to avoid huge MP point-and-shoot cameras: something called the Airy disk.