How good is your low light/color vision?

Mrs Guru sees color subtlety that would stump a color scanner but she also tends to run into things at night without at least one light per room. Like dogs who can't see certain colors but see well at night, she is the exact opposite. This got me thinking. Our eyes see with cells called rods and cones. Rods see low light and details better but can't see color, cones handle color but need more light.


Questions I want to answer with this survey:

1) CPFers prefer more light, do we have worse night vision as a group?

2) Is there an inverse correlation between night vision and color vision?

3) What is the level of awareness of our own perception?


Additional Reading
http://en.wikipedia.org/wiki/Rod_cell
http://en.wikipedia.org/wiki/Cone_cell

I have an undiagnosed but suspected retinal disorder now but back when I could see 20/20 or even picking off some of the 20/15 letters, I had a slight color blind disorder mainly in the brown/red domain and never had great night vision, not sure if it is related or not. From what I've read night vision decreases with age in almost everybody.

2) Is there an inverse correlation between night vision and color vision?

I have some background on this you may find usefull.

There is a tradeoff between good color vision and good night vision. There is only so much room in a given eye and the more of one type of cell you have, the less room there is for the other. Statistically, women have more cones and men more rods. This gives women a natural edge for color perception and fine detail, and men the edge in night vision. No one knows why we are built like this. There is variation from person to person. A given woman could have good night vision, a given man could have a good eye for color.

Dogs will outperform any human in night vision because they have something called the tapetum lucidum:

http://en.wikipedia.org/wiki/Tapetum_lucidum

The tapetum lucidum being a mirror like layer in the back of the eye that bounces back stray photons so they get a second chance to stimulate a sensor. Animals that are active in the day tend not to have this because all that light bouncing around in there can fog your day vision.

All persons tend to lose vision, especially night vision, with age. This is because the cornea tends to lose clarity and grow yellowish with time. The noticable effects of this are that older persons may have trouble with fine print, may want more light for a task than before, and may stop driving at night because they realize that they can no longer do it well.

Men get odd variations in their color vision, women usually do not. We call this color blindness and think of it as a defect. I personally suspect this is a feature, not a bug, that it was handy to have a man in your hunting or war party with slightly different vision, because that person could see through camoflauge where normal eyes would not.

I did a comparison with my wife yesterday night and we both see about as well and with similar color perception. I see pretty well in the dark but only in shades of gray.

What I find interesting about night vision is how you can see lots of stuff with your peripheral vision (fading GID, afterglow of a TV set, shapes and objects) that completely disappears when you try to look at it directly.

ElectronGuru asked me to post here a message that I posted earlier in another thread (which lights to bring on a night hike): https://www.candlepowerforums.com/threads/174055 )

Here is the message I posted:

Did you know that people who are colourblind have better night vision? It was in a newspaper a few years ago in the scientific section of the NRC (good reliable Dutch newspaper)

Found the article and quoted and translated a part of it:
The NRC article is of 22nd of August 1998 with the title:
'Kleurenblinden zien beter in het donker dan kleurenzienden'

Seeing colours happens with light sensitive cones in the center of the retina. Watching in darkness happens with small sticks that have a higher density along the border of the retina. The people who did the test were students of which 13 were colourblind. The students that did the test first had to look at a white filter for two minutes to give everyone an equal starting position. Then they looked into a small hole (9 by 9 cm) in the door of a dark room in which a light was burning. In front of the light was a colourfilter (six different colours were measured) and a changing number of filters with which the light was protected. Every minute in a session of half an hour the students had to indicate if they could distinguish the lamplight from the darkness in the dark room. In that time they got better used to the darkness.

The 13 colourblind students (2 women, 11 men) needed three times less light (with all colours tested) in order to distinguish the lamplight. They clearly distinguished themselves from the others of the group.

In addition, from the same article: It is common that first grade students Biologica of the Uni of Groningen (Neth.) test eachothers ability to see colors and the edge of the ability to distinguish light from absolute darkness.

From 1991 till 1996 the test results of 326 students have been saved. (13 of them were colorblind)

In general life:
8 percent of all men are colorblind.
1/4th of a percent of all women are colorblind.

iapyx

My wife is blind as a bat in the dark. (Turns on every damn light in the house just to go from one room to another. Drives me nuts)
I can probably navigate the house with only the low level night lights we have on.