The flash of a camera is bright enough to cause a reflection off the human
retina -- the red we see in these photos comes from the blood vessels in the
eye. Learn more about red eyes and cameras in this HowStuffWorks podcast.
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The flash of a camera is bright enough to cause a reflection off the human
retina -- the red we see in these photos comes from the blood vessels in the
eye. Learn more about red eyes and cameras in this HowStuffWorks podcast.
Learn more about advertising on the HowStuffWorks podcasts at
[www.howstuffworks.com/advertisers.htm](http://www.howstuffworks.com/advertisers.htm)
And to learn about your ad choices when listening to podcasts, visit
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