Why do people have red eyes when you take a picture??

When we take picteures the light that the flash and the ligt reflects off the retna and that causes the red ness that we seee when we get pictures taken. All animals such as dogs, cats, deers, and many more animals have a protective layer on thier eye called the "calledtapetum lucidum". When light is flasahed in to them a whit glow reflects off them. That is why if you take a picture of your pet you see that their eyes are weired and are all white. The red that you actually see is the blood vessel that makes your eye red. So the people that made the cameras now made a camer that reduces the redness in your eyes. What they do is make he camera flash two times so that your pupile will turn less red and the second one is so after your eye isn't so that it takes the picture.In my opinion I think tha is a good idea because know the people in their pictures can look pretty and not look so scary.















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