Guest Posted February 10, 2011 Posted February 10, 2011 Cats never co-operate. I'm surprised you got that good of a picture of him I think that cats have the TL that is mentioned in those research articles and is responsible for the red/yellow reflection. I am still curious about 17 X 7's eyes, I wonder if he has the "glow" and doesn't know it......
Guest ChrisBFRPKY Posted February 10, 2011 Posted February 10, 2011 Well, if you ever get some drops to force the pupils to dilate open, you might be able to get some eye shine from a human with that spotlight. That would be an interesting experiment. I can't perform it though as I don't have the drops to dialate my pupils and I don't wear glasses, so a checkup at the eye DR is out for me. If human eyes can reflect a red eyeshine when dialated, possibly the creature's eyes could be similar to ours in that case. I guess it could be possible for the creatures to have some sort of genetic trait as a result of their environment that their eyes could dialate fully after dark? Depends on what color eyeshine our eyes would have (if ours do show eyeshine when dialated) Wow! Alot more questions. I think I'll stop in the local Optometrist's office later today and ask him. This is too good to pass up. Chris B.
17x7 Posted February 10, 2011 Posted February 10, 2011 I am still curious about 17 X 7's eyes, I wonder if he has the "glow" and doesn't know it...... OK, I had to wait for dark (I'm half a day ahead of you in the States). I ran a couple of experiments. 1) Turned out the light in the bathroom for about 5 minutes and then had someone open the door and look at my eyes. Only light was a dimly lit hallway. No glow. 2) Repeated above except a flashlight was shone into my eyes this time. Still nothing. Only thing noted was that my pupils shrunk "real fast". I think I now know how a moth feels while circling the bulb and it took some time for my eyes to readjust to the brightness of this computer screen in a dark room. Sorry, but no glowing orbs here. 17x7
Guest Posted February 11, 2011 Posted February 11, 2011 Oh, that's alright, was just wondering since you have some visual traits that are out of the norm. Thanks for trying though, my curiosity is satisfied
Guest ChrisBFRPKY Posted February 11, 2011 Posted February 11, 2011 Followup from my visit to the McPeak Vision Center in Glasgow Ky: 1. Q: Do humans have any sort of eyeshine (similar to an animal's at night) when fully dialated by chemical means? A: Certainly not. 2. Q: Have you ever noticed any sort of reflection of light from the eyes of any of your patients in the past? Dialated or not. A: Nothing that would seem to compare with what you're asking. Now a patient that is presurgical for cataracts will reflect some light but I'm not aware of any color change of the reflected light. 3. Q: Is that the condition where the cataract makes the eye look kinda white in color? A: Yes, exactly. So, my findings: No eyeshine in humans dialated pupils or not. Chris B.
Guest Posted February 11, 2011 Posted February 11, 2011 Thanks Chris, I figured not, but better to ask an expert. I wonder if the little wolf girls from India had cataracts? It kind of fits the description they gave of how their eyes shone in the dark and that they could not see well during the day.
Guest ajciani Posted February 11, 2011 Posted February 11, 2011 It's good to ask the optometrist, for the eye drops to try it yourself. Most optometrists would never see a patient (dilated or normal) in the conditions necessary for eye shine. The retina definitely does reflect red light. That optometrist has probably just been too busy looking at that reflection through an instrument to notice the reflection. Kind of like not seeing the forest because of the trees. Also, that kitty's pupils were about 11 mm across, maybe even 12 mm. His eyes will not glow like that if the pupils are a little narrower. Then again, I rarely ever see his pupils narrower at night. I think that cats have the TL that is mentioned in those research articles and is responsible for the red/yellow reflection. In felines (that have them), the tapetum lucidum causes a yellow-green reflection. This particular kitty is a Siamese, and the TL in the Siamese is either not present or diminished. The red glow is just the reflection of light from the blood and membranes of the retina. It is actually rather hard to get his eyes to shine in the normal kitty way. They only just glow red. I do have a tabby cat that has a TL, and his eyes do not shine red like that. His pupils usually stay a bit more narrow, so the only time you can see any shine from them is if he is in a very dark area, and there is a light shining in. Because of the TL, his shine a bright yellow-green.
Guest Posted February 11, 2011 Posted February 11, 2011 It's good to ask the optometrist, for the eye drops to try it yourself. Most optometrists would never see a patient (dilated or normal) in the conditions necessary for eye shine. The retina definitely does reflect red light. That optometrist has probably just been too busy looking at that reflection through an instrument to notice the reflection. Kind of like not seeing the forest because of the trees. Also, that kitty's pupils were about 11 mm across, maybe even 12 mm. His eyes will not glow like that if the pupils are a little narrower. Then again, I rarely ever see his pupils narrower at night. In felines (that have them), the tapetum lucidum causes a yellow-green reflection. This particular kitty is a Siamese, and the TL in the Siamese is either not present or diminished. The red glow is just the reflection of light from the blood and membranes of the retina. It is actually rather hard to get his eyes to shine in the normal kitty way. They only just glow red. I do have a tabby cat that has a TL, and his eyes do not shine red like that. His pupils usually stay a bit more narrow, so the only time you can see any shine from them is if he is in a very dark area, and there is a light shining in. Because of the TL, his shine a bright yellow-green. I had no idea. I would think all cats would have them.I think I know what you are talking about as far as human eyeshine. It might be because the optometrist is either right up in your face or has that lens machine between you and his face. But when they shine that light in your eyes you see a red flash and then the vessels of your eye, which is weird because you are seeing the inside of your own eyeball. Is that what you are talking about?
Guest ajciani Posted February 11, 2011 Posted February 11, 2011 Basically, yes. We know that human eyes can shine (or glow) red. We see it in flash photography. The question is, if a human pupil were wide enough, would we be able to see it when someone is standing in the dark looking toward a light. An optometrist's office just isn't going to have that happening, and most of the time, he would be looking through some type of instrument into the eye. It may also be that the optometrist simply hasn't noticed a faint glow, but it happens all the time. There is also the possibility that a human eye simply cannot dilate wide enough to let enough light in for eye shine in any non-flash condition. I think my iris is as big as my cat's pupil. There is just no way to make my pupil as large as his.
Guest vilnoori Posted February 12, 2011 Posted February 12, 2011 By the way that was a really cool pic of your cat, aj. I have a cat that looks like that, too. He is a siamese cross, with light blue eyes and a dark face, but he has a white nose and chin and white "booties." Cute as the dickens.
bipedalist Posted February 13, 2011 BFF Patron Posted February 13, 2011 Thought I'd just throw in a raccoon video targeted at a feeding/bait station (hanging peach basket). It shows how Sony supernightshot video (secured by tripod and unattended) with a couple of booster IR lights attached can bring out reflected light from the tapetum lucidum for those who have never seen it live. Also, I have seen the same characteristics with opossum on IR game cam shots at night. Might have some of those too, if I can dig those up I'll post as an edit or follow-up. I'll throw a link over to the bait-station thread too. The topic of concern (eyeshine) can be seen beginning about 6:20 through near 9:00 minute mark as I remember to speed things up.
bipedalist Posted February 14, 2011 BFF Patron Posted February 14, 2011 (edited) Eyeshine in opossum(one of the critters with tapetum lucidum). As added humor, there's a lot of eyeshine in Brooklyn I hear: Edited February 14, 2011 by bipedalist
Guest ajciani Posted February 14, 2011 Posted February 14, 2011 Actually, you can see some serious eye shine from humans in the near IR too. Because our eyes don't see it, our pupils stay dilated. Our eyes also reflect better in the far red and near IR. It isn't a tapetum, but it might be a reflective mechanism to keep our eyes from getting burned by radiation we can't see. Interestingly, when the human eye is seeing something, the NIR reflectivity of the fundus decreases.
Guest DWA Posted May 26, 2017 Posted May 26, 2017 Most of the answers I am seeing here are using information it will be useless to speculate upon until there is a specimen. How do they see in the dark? Well, they exhibit eyeshine, which humans don't, but which animals with good night vision do. The bet here is that when this is examined up close and firsthand, we'll find sasquatch adaptations to night vision to parallel those of other mammals exhibiting eyeshine.
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