Cones are more prevalent in the central visual field. While rods and more prevalent in the peripheral visual field.
Cones are let you see colours, however they are less sensetive to dim light
Rods are sensetive to dim light, they let you see mire greenish colours and help you see in the dark.
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Thinking about it, it makes sense that in the dark our peripheral vision is better than our central because it alows us to pick up motion better.
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Also I've noticed that in the dark my central vision is poorer than my peripheral.
Also clear flashes in day light is much better and FAR more prevalent.
What do you think bout this? My question is,
If you agree with this
-Wouldn't centrally fixating cause strain in the dark?
My understanding is that central fixation is a property of healthy vision rather than an action that the eyes can execute. I think that the fact that the cones aren't as sensitive in dim light would mean that the resulting image would be less sharp even if you weren't straining. If you are straining though, I think chances are good that the image would be even less sharp - which is why many people with imperfect vision tend to have problems seeing anything at all in the dark.
As for what qualifies as dim light, my guess would be that it's a gradual progression from bright to dim. It's a complete guess on my part, but it doesn't seem logical to me that there would be a certain intensity of light at which the cones would "turn off", so to speak.
You still have to use your eyes normally as you would in brighter light, paying attention to your central vision. The result will just be a little different, in the sense that the portion of information coming from further away from the center of vision will be greater.
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"Half of our funny, heathen lives, we are bent double to gather things we have tossed away." - George Meredith
I don't know what answer your mother gave to why you needed to look to the side of something in dim light to see it more clearly. It's because the center of vision in the humn eye, the macula, is all cones, which shut down when there's too little light. Chicken eyes have all cones, no rods, so chickens are blind in the dark. When driving at night you can sometimes see a dimly-lit sign more clearly if you look to the side of it. No straining!
