Talk:Red-eye effect

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I changed the part of this article that mentioned the lens of the eye focusing light from the flash onto the retina. In fact, most of the focusing done by the eye is not done by the lens. Instead, the change in index of refraction from air (N=1) to liquid (N=1.3) does most of the focusing. The index of refraction for the lens is about 1.45 and thus it does focus light, but due to its thickness compared to that of the entire thickness of the eye it is not the primary focusing agent.

I'd need to ask the person I took the picture of for her permission (although I don't *need* it) before I'd put it on the wikipedia, but I got a textbook example. [1] Ich 08:45, 19 July 2005 (UTC)

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As I recall, different species have different colours of "red eye". Does anyone know about this?

Well, the picture I uploaded for this page is a bit more yellow-eye than red. I have a better, non-animal, example - but need to persuade the subject to allow a very bad picture of him to be used on-line ;) I also have a picture of a cat with bright-green-eye that might be useful. -- sannse 20:12 Mar 30, 2003 (UTC)

This is a brilliant (no pun intended) page. Is it possible to add info on HOW to avoid it by flashgun angle? That would be v useful to duff photographers e.g. me. OK sure you don't get it with a bounce flash head, but how can you judge what separation is needed if you are pointing the flash at the subject? Is it distance related?? etc etc etc. Thanks in anticiaption, Nevilley 18:18 Mar 31, 2003 (UTC)

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The image of the dog shows more vividly the red eye effect than the image of the man. Why not use the dog picture? Or, if you're married to the idea of a human image, find one that shows the effect as vividly as the dog image. IMHO, Kingturtle 09:31 Apr 20, 2003 (UTC)

The dog picture was better. Ericd 09:37 Apr 20, 2003 (UTC)

The problem with the dog image is that it doesn't show red eyes, they are more yellow and I feared that that the colour was from a slightly different effect (reflection from the tapetum lucidum rather than the blood in the retina). I am intending to replace the image with a better example as I find one (unless someone else finds one first of course), but I thought it better to have the more appropriate image for now. If you both disagree I'll put the dog back until I find a better human example. -- sannse 09:43 Apr 20, 2003 (UTC)

Well I see your point. The dog picture is probably more effected by the dog's inner eye reflection. But surely we can find a photo that better shows the red-eye effect. Kingturtle 09:48 Apr 20, 2003 (UTC)

I'm sure we can. This was the best I had, I tend to throw out or edit any that have red eye. Next time I'm in a dark room with a flash and a suitable subject I'll try and get a better one. Or perhaps someone else has a good example? I've reverted to the dog for now. -- sannse 09:57 Apr 20, 2003 (UTC)

There's one I took with my digital (the cheap kind; ironically it's supposed to suppress redeye). It's not very clear though. Hephaestos 10:04 Apr 20, 2003 (UTC)

Excellent! Kingturtle 10:07 Apr 20, 2003 (UTC)

Good example, thanks -- sannse 10:11 Apr 20, 2003 (UTC)

Waooohhh wonderful example. The "best" red eye effect is achieved with children and animals adults often look elswhere to avoid the flash. Ericd 11:25 Apr 20, 2003 (UTC)

[edit] Dead men show no Red Eye

Anyone know why dead People don't have a red eye effect? THis could be a nice addition to the article...

....mostly because their eyes are closed. Also because dead people don't often feature in holiday photos (except in Rhyl), but mostly because there is no blood in the blood vessels behind the retina so you ought to get a grey-eye effect. Any examples out there ? Mrs Trellis 09:46, 19 July 2005 (UTC)

[edit] glowing eyes

So, red eye is noticable in photographs because the pupil has not had time to shrink in response to the light? Does this mean that lower levels of light also reflect back out of the eye from the retina, but we just don't notice it? (Infrared is also brilliantly reflected by the eye, but we can't usually see infrared.) I wonder, do other animals ever notice human eyes glowing under natural light; and do cats, for example, notice other cats' eyes glowing? Can people use the light reflecting from their eyes like a flashlight? Does the light reflected by the eye contribute to ambient surroundings?

[edit] statement under inset cat image is wrong

The inset image of the cat incorrectly states that the red-eye effect in cats is not red. Blue-eyed cats glow red and other eye colors glow green. Odd-eyed whites, for example, glow red in one eye and green in the other. Greg [[User_talk:Evilgreg3000|(Talk)]] 02:40, 1 January 2007 (UTC)