I remember a couple professors telling me that the human eye is most sensitive to blue light. I have heard the argument that the human eye is most sensitive to red light as well and I objected...but from a different POV...this could be considered true.
I see in your Reefkeeping segment, that you say 550nm/green is what human eyes are most sensitive to. Hmmmm...yet another curveball.
Now, Im not trying to argue here...Im civil, you are the Professor, but it seems that this subject has come up for debate a few times depending on who you talk to...so I was hoping to have a discussion with you Sanjay, to gain a better understanding if nothing else.
The argument I have heard for red light being the spectrum our eyes are most sensitive to is from professional photographers...so there might be a lack of radiometric measure for exact verification...but their opinion is based on when they fire up a 1000watt tungsten filament bulb, this is the brightest bulb they know of. For some daylight settings, they use bluer 1000watt halide bulbs, but they say that the halide is no where near as intense to look at. This is kind of odd since the PAR of a tungsten should pale in comparison to that of a halide, right? Yet the tungsten looks brighter...hmmm.
The argument for blue light being the one our eyes are most sensitive to is based on a few things. First, nightvision. Blue light is used by BMW to provide the best supplimental light with those xenon headlights...a frequency that we are most sensitive in low levels, yet of a spectrum that doesnt disrupt our nightvision. How are we most sensitive? Well, unlike other frequencies, the concentration of cones in the fovea centralis that actually pick up blue light are only 2% (and 32% green sensitive cones, and 64% red cones). This is because blue light is part of our perception of what daylight is...and our rods actually pick up blue frequencies rather than our cones. So the argument can be made that since there are only 2% of our cones that pick up blue light, these must be the most 'sensitive', or we would hardly be able to see blue light in comparison to all the other spectrums. And since blue light is linked to our perception of brightness more than with red or green frequencies, it could be said that blue light is what we are most sensitive to. Of course, the fact that 64% of our cones are attuned to red light suggests that red light is what we are most sensitive to...so what I am trying to get at is that it alll depends on how you interpret the data. Lets say you have a color blind person...their lack of cones would mean that the only color they see and interpret as brightness would be blue light, as rods pick up blue. This is also why blue light is so great for nightvision...it allows us to see by giving us a 'daylight' or sorts without triggering our cones. So I suppose the bottom line to this argument is that since rods see blue light, and no other frequencies, as daylight, we would be most sensitive to it since not only do our cones 'see' it, but so do our rods. Blue light has more to do with what we consider 'brightness' than other frequencies.
But this might only be true of lower intensity situations. As a lights intensity increases, it appears that our rods will take the back burner to the cones and the cones interpret the color...and then its all up for grabs. But blue light could be argued to be the color we are most sensitive to.
Here are some of my sources...
http://hyperphysics.phy-astr.gsu.edu...bright.html#c2
http://hyperphysics.phy-astr.gsu.edu...n/rodcone.html
http://www.rwc.uc.edu/koehler/biophys/6d.html
There was also the evolution based argument, based not on the eye, but how our brain interprets the data. It suggests that red is the most 'vivid' since in our evolution red means blood...pain, injury, fighting, warning, or food. Blue is less 'alarming' to us since it represents sky and maybe water...two things of little consequence in our daily survival. Green would also be the most common...leaves and trees would be green all over and so would the grasses...also of little inportance. Of course, this is a more having to do with perception than what we see...
Whats your take on the info? I still dont quite see how you came up with Green as the most sensitive as far as our eyes see... I can see how arguments for red or blue originate depending on the brightness of the light...but green?