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Taking my current profile picture as a prominent example:

Dog's eyes glowing green in camera

This photo has been taken with flash. As I gather, this is the same effect that makes a human's eyes glow red on photos, namely the reflection of the flash at the choroid and then passing back through the retina.

The retina is full of bloodvessels and the blood inside them gives the reflected light it's reddish color.

If it's the same effect, why is the color different?

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  • $\begingroup$ Come on that's photoshopped $\endgroup$ – rhill45 Jan 13 '15 at 18:17
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    $\begingroup$ Nope. Not at all $\endgroup$ – Vogel612 Jan 13 '15 at 18:17
  • $\begingroup$ Then it's a star wars dog or you got some weird camera thing going on. Try post another with a person looking at the camera and that will rule out the camera thing. User 137 is right below but I've never seen something like this. $\endgroup$ – rhill45 Jan 13 '15 at 18:22
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Dogs, cats, and many other mammals have a Tapetum lucidum which reflects light back through the retina to help with night vision. Humans don't have this layer. The tapetum is probably reflecting green light that would have normally been absorbed.

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    $\begingroup$ The rod cells - cells used for night vision - are the most sensitive in the green region of spectrum. It does make sense for tapetum lucidum to reflect these preferentially $\endgroup$ – John Dvorak Jan 12 '15 at 18:21
  • $\begingroup$ It's also interesting that different dogs can reflect different colors. My Border Collie mix reflects greenish, but my (probably) Plott Hound reflects blue. (This is with an LED headlamp at night, not camera flash.) $\endgroup$ – jamesqf Jan 12 '15 at 19:35
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    $\begingroup$ @jamesqf Sometimes 1 animal can do two colors at once. $\endgroup$ – user137 Jan 12 '15 at 19:38

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