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Old Jan 4, 2004, 11:07 AM   #11
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The red color comes from light that reflects off of the retinas in our eyes. In many animals, including dogs, cats and deer, the retina has a special reflective layer called the tapetum lucidum that acts almost like a mirror at the backs of their eyes. If you shine a flashlight or headlights into their eyes at night, their eyes shine back with bright, white light. Here is what Encyclopedia Britannica has to say about the tapetum lucidum:

Among many nocturnal vertebrates the white compound guanine is found in the epithelium or retina of the eye. This provides a mirrorlike surface, the tapetum lucidum, which reflects light outward and thereby allows a second chance for its absorption by visual pigments at very low light intensities. Tapeta lucida produce the familiar eyeshine of nocturnal animals.

Humans don't have this tapetum lucidum layer in their retinas. If you shine a flashlight in a person's eyes at night, you don't see any sort of reflection. The flash on a camera is bright enough, however, to cause a reflection off of the retina -- what you see is the red color from the blood vessels nourishing the eye.

Many cameras have a "red eye reduction" feature. In these cameras, the flash goes off twice -- once right before the picture is taken, and then again to actually take the picture. The first flash causes people's pupils to contract, reducing "red eye" significantly. Another trick is to turn on all the lights in the room, which also contracts the pupil.

Another way to reduce or eliminate "red eye" in pictures is to move the flash away from the lens. On most small cameras, the flash is only an inch or two away from the lens, so the reflection comes right back into the lens and shows up on the film. If you can detach the flash and hold it several feet away from the lens, that helps a lot. You can also try bouncing the flash off the ceiling if that is an option.

from:
http://science.howstuffworks.com/question51.htm
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Old Jan 4, 2004, 12:03 PM   #12
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Thanks for the reply. I'm pretty much aware of what causes it, and how to get around the problem. The built in flash that is close to the lens is the big problem on the compact cameras.

What I'm wondering, is since the pop up on the EOS Rebel G SLR film camera never gave me any red eye issues, would the Digital Rebel with the similar design perform as well?
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Old Jan 4, 2004, 1:31 PM   #13
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The DRebel's onboard flash can be a problem, but not as big of a problem as the compact cams. It's probably in line with your current camera. It does have an option to turn RED EYE Prevention on or off. I normally use an external flash with my DR, so I can't comment on the occurance of red eye with the popup flash.
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Old Jan 4, 2004, 2:14 PM   #14
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Default Thanks for all the great info!

Thanks for all the great info! I'll definitely study all your comments. I know I've got plenty to learn... I'm hoping to find the camera that forgives my ignorance right now!

There is a photo on the People Photo forum... "Christmas in a childs eyes"... taken with the Digital Rebel. Awesome!

Thanks again for helping me!
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Old Jan 4, 2004, 11:31 PM   #15
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Okay... done a little more research and found a surprise...

someone posted a site that compares test photos...
http://www.imaging-resource.com/IMCOMP/CDISPLAY.HTM

I looked at the canon digital rebel test photo for the indoor flash ... and it is blurry!???? (click twice to see the full picture not the two thumbnail size ones) That doesn't make me too comfortable... knowing the expense of this camera.

I studied that site and it seems he likes the Olympus C-5060 ... the test image looks clear. I've studied on this forum and it appears it gets good remarks and some think the C-5050 is better for low light. The test images compared shows the C-5060 clearer IMHO.

Sorry to be confused again. Anyone have a comment on test photos? or cameras?

Thanks again!
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Old Jan 5, 2004, 10:46 AM   #16
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The blurry pictures your seeing may not necessarily be a problem with the autofocus - but could be camera-shake - especially if you are zooming beyond 2X.
I recently bought the Minolta DiMAGE A1 - and one of the big reason I selected it was because I saw problems with blurry images using other large-zoom cameras. The A1's antishake features shifts the CCD while taking the shot to correct this problem. You may want to consider the A1 amoung your choices if you haven't done so thus far.

There is a lot of talk about Red-Eye - I often times leave the read-eye turned off on my A1 since it often times causes me to miss the shot I'm trying to get (due to the delay with the flashes it uses to dialate the subject's eyes). I have never minded correcting for red-eye later using software. The only time I turn it on - is if I am taking posed portrait shots - in which case the A1 seems to be okay.
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Old Jan 5, 2004, 10:50 PM   #17
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Default thanks!

Thanks for the information! I'll check it out.

I know it is me not the camera causing the shake... and the blurred picture to follow. I think a bigger camera... more SLR like might help too.

I'm sure that site above with the Digital Rebel out of focus is a mistake... but strange.

I would love to see a test photo with the camera hand held and people moving! I tried this at the camera store tonight with the few that had power and the ability to look back at the photo. The Sony Mavica CD500 seemed to do well. Someone came by to buy the CD350... they didn't have it. He had one in the past and was really in love with the features.

I'm still researching...

Thanks for that stablization tip!
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