Do you have red eyes? Or are they blue, brown or hazel? Of course, regardless of what color eyes you have, you may look like you have red eyes in photographs from time to time.
Have you ever had your picture taken and noticed afterward that you look like an alien or a zombie with bright, glowing red eyes? This is called the “red-eye effect.”
Although it looks magical and somewhat sinister, there’s a reasonable scientific explanation for it. So what causes your blue (or brown or hazel) eyes to turn red in certain photographs?
The red-eye effect happens when flash pictures are taken in low-light situations. When the flash is located close to the camera lens (as it is in most cameras), you may be looking almost directly at the flash when you look at the camera lens.
The red-eye effect results when the light of the flash occurs too quickly for the pupil of the eye to close. The bright light of the flash passes into the eye through the pupil, reflects off the retina at the back of the eyeball and returns back out through the pupil.
The camera records this reflected light. It appears red because of the amount of blood located in the back of the eyeball.
The red-eye effect tends to be stronger in people with light eye colors, light hair colors and fair complexions. Scientists believe this is because these people have less melanin in their eyes. Melanin helps to reduce the red-eye effect to some extent in people with darker eyes, hair colors and complexions.
If you have pets, you may have noticed that the red-eye effect can be quite different in animals. Animals have a special reflective layer at the back of their eyes called the “tapetum.”
The tapetum helps to enhance night vision. Depending on the animal, the tapetum can cause a blue, green or yellow effect on the eyes.
If you want to reduce the red-eye effect when taking photographs, here are a few helpful tips to follow:
- Turn on more lights and avoid using the camera’s flash, if possible.
- Use an external flash with your camera so that the flash is farther away from the camera lens.
- Use the red-eye reduction feature if your camera has it. This feature uses the flash repeatedly before taking the picture, which gives the pupil time to contract.
- Have your subject look away from the camera lens.
- Use graphics editing computer software to remove the red-eye effect digitally after the photograph is taken.
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Hey Wonderopolis! If you stand near something like a hamster that is in direct sunlight, does it look like it has red eyes? Thanks! See ya.
We’re not sure about that one, Evan! We’ll have to do some more WONDERing! Because the sunlight is constant, and not a “quick” flash like that from a camera, it would be interesting to find out if the special “tapetum” that animals have in their eyes causes a strange effect in just bright sunlight! Thanks for thinking more about this Wonder after you were done exploring it!
We just love taking pictures!!
We like to post our pictures on Facebook to share with our friends. We also talked about things we do with our pictures such as keep them in photo boxes, picture frames around our house, or even scrapbooking…. We liked having tips for getting rid of red-eyes. One of our teachers said her camera flashes twice as part of its red-eye reduction option.
Happy Friday, Kerrick Elementary School! We’re so glad you talked about ways you can share pictures, and we’re glad you shared your awesome comment with us! Thank you for visiting today’s Wonder!
I have hazel eyes, but they can get very light because my mom has light blue eyes. I only get the red-eye effect when I take a picture on a day when my eye color is fairly light. Does that make a difference? My sister gets red-eye effect way more than me and she has Dark Brown eyes. Why does that happen? Thank you!!
That’s very interesting, Autumn! Even though the “red-eye effect” is supposed to be lesser in people with darker eyes and complexions, it all depends on the person! There are exceptions to some rules, and maybe your eyes and your sister’s eye are just extra awesome! Thanks so much for your comment today!
Red eyes are freaky!
We think it was cool to learn what causes them in pictures, though, didn’t you, ASD? Thanks so much for leaving us this comment today and for letting us know what you think about red eyes!
Wow, wonderopolis! I never really took the time to wonder about this, and I always thought that this whole red-eye was a technology problem. Who knew your eyes could turn red? Thanks and keep wondering!
Hello, Nitnik! We’re so glad you stopped by Wonderopolis today and left us this great comment! Thanks for letting us know that you learned something new from this Wonder about the red-eye effect! We’ll keep WONDERing every day if you will, too, OK?
Hey there, Wonderopolis crew! I think that red eyes are interesting to learn about. But, then again, almost everything on here is fun to learn about! If you took a picture of a person who has white eyes would the red eye affect affect them? Thanks!
Hello, Abby! It’s GREAT to hear from you again! That’s a really smart question about the eyes. We’re not sure what would happen, as we’ve never seen anyone with a complete lack of pigmentation in their eyes. Let’s do some more WONDERing about that, OK?
Are red eyes bad?
Hi, Blake! If you’ve got red eyes when you look in the mirror, it might mean you’re sad (and you’ve been crying), you have allergies, or you haven’t had enough sleep, and NONE of those sound like fun to us! Red eyes in photographs aren’t really “bad,” but lots of Wonder Friends wish they didn’t show up when they look at their pictures!
I liked learning about red eyes. I learned a lot. By the way,how do you come up with all these wonders? From Charlie, Ryne, Anaya, and Serean.
Thanks so much for leaving us a comment to let us know you visited this Wonder of the Day® today, Charlie, Ryne, Anaya and Serean!
Did you know that this Wonder was actually the idea of a Wonder Friend just like YOU? It’s true! One of our AWESOME Wonder Friends let us know what they WONDERed about by clicking on the “nominate” link that’s found at the top of every page in Wonderoplis and answering a few easy questions! It’s FUN to nominate ideas for future Wonders…we hope you’ll give it a try, too!
:-)
I don’t get why a red eye is bad…..
I had a red eye in a picture before, but I wasn’t sad or feeling bad.
Plus, I have no allergies.
That’s a great point, Moa! Some Wonder Friends might not be upset when their eyes appear red in photographs. We just WONDERed why that effect happens, so we thought it would be a FUN idea for a Wonder of the Day®! Thanks so much for sharing your comment with us…we appreciate you!
That’s a great idea for a wonder! I’m trying to show my dad. I wish I had a cool website!
Thanks for your comment, Ria! We’re super excited that you and your dad are going to Wonder together– keep up the great work! We Wonder if you have an idea for a website of your own already?!