Rig for Red Question.

Okay so I know that reason for the red light is to let your eyes adapt to be ready for night watch, but what Im curious about, is do any of you know the specifics of WHY red light helps adjust your eyes for night vision?? Im just curious that is all

[frau kaleun]

I have no idea if this is scientifically accurate, but I found this in the forums at uboat.net:

http://www.uboat.net/forums/read.php...3302#msg-63302

Scotopic and photopic vision. Rods and cones receptors are in the retina of the eye. For daylight vision we humans use what is called photopic vision that being the cone receptors. With them we see color. With bright light the rods are inactive, that being they are switched off. In the dark the rods become active and we see in shades of gray. The rods are not affected by red light consequently the red light in the cabin. The rod light sensitivity cuts off at about 620 nanometers. The cone light sensitivity cuts off at about 700 nanometers. Red light energy starts beyond 620 nanometers therefore it does not switch the rods off. When looking at a dark sky rod vision is very effective and cone vision is not.

[desirableroasted]

It is accurate, though I cannot attest to the science.

When I used to sail, I covered the flashlight with a thick red gel sheet to keep my vision. Also as a teenager when astronomy was my passion. I was told that was what I should do to "keep vision."

It sure does work.

Are there any other colors that do that? I saw that american submarines rigged for blue instead of red??

[Gargamel]

I think that's to reduce fatigue, as there isn't as much of a need for night vision in the modern sub.

Red is the best color for preserving night vision.

Originally Posted by Gargamel

I think that's to reduce fatigue, as there isn't as much of a need for night vision in the modern sub.

Red is the best color for preserving night vision.

I think I even read though that WWII American subs rigged for blue though.

[Gargamel]

I do not know then.

I'd check the SH4 historical facts sticky thread. They may have already answered the question there.

[kroll688]

Until recently, that is within the last few years, US submarines rigged for red. I have toured the Bowfin in Pearl Harbor and read many accounts from US skippers - O'kane, etc... They also used red lenses on goggles. Another item is to hang drapes around the scope area to keep any internal light sources away from the scope operator.