Doubts on function of cones and rods

[Page-David]

Hi, @leandromoreira, thanks for your detailed tutorial.

In Simplistic explanation of how our eyes work section, you mentioned The rod cells are mostly responsible for brightness while the cone cells are responsible for color as why we are more sensitive to brightness. The conclusion is alright but, I think, cone cells also responsible for brightness and here is the words from wikipedia:

They(Cones) are responsible for color vision and function best in relatively bright light, as opposed to rod cells, which work better in dim light...
Cones are less sensitive to light than the rod cells in the retina... (That means cones also sense light, does not?)

I believe cone cells also responsible for light when the surrounding is bright enough. If rods also works in sunshine, why eyes need take time to adjust when we go to a dark room? I think it's because rods do not work in brightness, so there is a "warm up" process to let rods work.

Cone cell - wikipedia

[leandromoreira]

Hi @Page-David =) Thanks for the clarification, I really wanted to show that these two "cells" have distinct functions and that our vision is more concerned with brightness than color/finer details and how we can explore it.

[Page-David]

Eyes are less sensitive to color than brightness, I agree, is one of theories behind video compress. But I think why sensitive difference exists should not be explained by distinct functions and quantities as two cells do not work together at most time. I think what cause this phenomenon is hardly can be explained in a few words and it may relates to Anatomy or Biology.
I have not read any formal published English book on Colorimetry yet but I have read a Chinese book call this phenomenon as “色彩细节失明” (in English it seems to be "blind to color detail"). That book explain this with a experiment which shows 1mm diameter are required for people to see black details on white background while 2.5mm are required to see green details on red one.
Google shows Chinese book refer to this terminology quite often, but I have not found any corresponding word in English. Anyway, hope that helps.

[leandromoreira]

@Page-David indeed it helps =) would you mind to rephrase the setence to a more accurate one but still simple? I'd be happy to merge your PR.