Red light at night is a MYTH?!??!

[KP44]

Originally Posted by newhaul

If it were red the US Navy wouldn't use blue lighting in spaces where seeing every detail counts. Such as the combat information center.

The reason for red on deck is a millitary one it doesn't Cary when dim. Blue is the best . As it does not impair the eyes ability to see white light , like red lighting does.

Very dim light allows a swifter recovery of night vision. Green or full spectrum and very dim is better.
We used red in dark-rooms because the long red light did not expose our photographic papers for black & white printing. I think the myth of red light and night vision carried over from black & white photo printing.

Scotopic vision is the vision of the eye under low-light levels. In the human eye, cone cells are nonfunctional in low visible light. Scotopic vision is produced exclusively through rod cells, which are most sensitive to wavelengths of around 498 nm (green–blue) and are insensitive to wavelengths longer than about 640 nm (reddish orange)

Mesopic vision occurs in intermediate lighting conditions (luminance level 10−3 to 100.5 cd/m2) and is effectively a combination of scotopic and photopic vision. This gives inaccurate visual acuity and color discrimination.

In other words, we need considerably higher levels of red light than green-blue light. (Or full-spectrum light.) Red night-lights keep us in the mesopic range instead of truly scotopic (dark night) vision.

If you see the light as "red" (or green), you are not using scotopic vision.

[newhaul]

Originally Posted by KP44

Very dim light allows a swifter recovery of night vision. Green or full spectrum and very dim is better.
We used red in dark-rooms because the long red light did not expose our photographic papers for black & white printing. I think the myth of red light and night vision carried over from black & white photo printing.

Scotopic vision is the vision of the eye under low-light levels. In the human eye, cone cells are nonfunctional in low visible light. Scotopic vision is produced exclusively through rod cells, which are most sensitive to wavelengths of around 498 nm (green–blue) and are insensitive to wavelengths longer than about 640 nm (reddish orange)

Mesopic vision occurs in intermediate lighting conditions (luminance level 10−3 to 100.5 cd/m2) and is effectively a combination of scotopic and photopic vision. This gives inaccurate visual acuity and color discrimination.

In other words, we need considerably higher levels of red light than green-blue light. (Or full-spectrum light.) Red night-lights keep us in the mesopic range instead of truly scotopic (dark night) vision.

If you see the light as "red" (or green), you are not using scotopic vision.

Sounds about right but in the dark room I did better work with no light at all

Just not printing pictures

[newhaul]

Here is another thread from a couple years ago that explains everything quite well

https://www.cruisersforum.com/forums...on-209780.html

[wholybee]

That red light doesn't affect night vision and/or it is faster to recover from is easy to test and verify. My issue is that I can't see under red-light well enough for it to be useful. I certainly can't read a chart, or see much of anything else. Even a red headlamp while on deck is difficult. I think it is related to 2 factors: age, and that red lights are now LED's. The usage of red lights started with incandescent bulbs, and I think they work much better then LED's for chartwork.

Anyway, it used to be that at night any white light was forbidden to be used. Now I have given up on that, as red lights have become useless for me to work by. I do still seem to have very good night vision once adjusted though. I just can't see well under the dim red light.

Also, why is it that every headlamp with a red light you have to turn-on at the brightest white light setting first, then after your vision is ruined you can turn it to red? That defeats the whole purpose of the red light.

[japawil]

http://stlplaces.com/night_vision_red_myth/

It seems that what is true of many long held debates; that it’s not always a black and white sort of situation but a more nuanced reality.

[Cadence]

Originally Posted by wholybee

That red light doesn't affect night vision and/or it is faster to recover from is easy to test and verify. My issue is that I can't see under red-light well enough for it to be useful. I certainly can't read a chart, or see much of anything else. Even a red headlamp while on deck is difficult. I think it is related to 2 factors: age, and that red lights are now LED's. The usage of red lights started with incandescent bulbs, and I think they work much better then LED's for chartwork.

Anyway, it used to be that at night any white light was forbidden to be used. Now I have given up on that, as red lights have become useless for me to work by. I do still seem to have very good night vision once adjusted though. I just can't see well under the dim red light.

Also, why is it that every headlamp with a red light you have to turn-on at the brightest white light setting first, then after your vision is ruined you can turn it to red? That defeats the whole purpose of the red light.

Drift, I wish I could still get incandescent bulbs. Broad spectrum.

[StuM]

Originally Posted by wholybee

Also, why is it that every headlamp with a red light you have to turn-on at the brightest white light setting first, then after your vision is ruined you can turn it to red? That defeats the whole purpose of the red light.

Yep, that annoys me too


There are a few that don't do that, but it appears that most are designed by people who don't understand how they are used.


https://www.amazon.com/VITCHELO-Head.../dp/B01AYDU2IW
The VITCHELO V800 headlamp flashlight is SUPER BRIGHT, you can see up to 360 ft (110m), and unlike most headlamps, it has 2 SEPARATE BUTTONS FOR THE WHITE and RED LIGHTS so you don't have to cycle through one to get to the other.

[TOMMYKAY9483]

Originally Posted by wholybee

Also, why is it that every headlamp with a red light you have to turn-on at the brightest white light setting first, then after your vision is ruined you can turn it to red? That defeats the whole purpose of the red light.

I thought the same thing. Frustrating.

[Aethelwulffe]

Yeah, you gotta cover the damn light as you cycle it. Me, I just use a version that utilizes a snap-on red cover.


In final passing, Blue light is used in ship CIC and aircraft because it is OK for night vision, and it works better with the ancient Hercules Monochrome "Green Screens" and ancient raster radar repeaters than red light. That is it. Period. It is a compromise, not because blue is better than red. Red is used on the bridge and attached chart room. Blue is perfectly legal to use there....red is absolutely validly totally better. I was a USN Signalman (topsider, visual communications and lookout rating) for over a decade, various other rates and billets as Needs of the Navy and CREO categories demanded, and a gunner's mate after that (once I went to the reserves). Forward deployed on FF-1082, AGF-3, MCM-4,7,8 and MHC-52. Also did a couple of SBU assignments in Bahrain. YEARS of time topside, on watch, snotty conditions, fighting CIC for the bragging rights of spotting a contact before bridge or CIC watchstanders found it, and lots of time in CIC or on the bridge as enlisted JOOD/Conn fighting the lookouts to spot stuff on radar before they did. Only game in town you know? Coming out of CIC in blue light, I still needed time for my eyeballs to adjust to the point where I could point out the glow of an OTH contact the forward lookout was missing.

[Aethelwulffe]

Originally Posted by Cadence

Drift, I wish I could still get incandescent bulbs. Broad spectrum.

Broad spectrum is broader than your ability to perceive it === wasted energy and thus less light per watt. White light is white light. If it is "white", it is pretty broad spectrum already, because, as you might note, it reflects in all the colors you can perceive...

[Cynara]

In the old days before LEDs any light bulb used a lot of power. At our chart table we couldn't just turn on/off the light, because any change like that would mess up your night vision. So we left a small kerosene light on over the chart table. Never hurt our vision. would give us some light down below. It worked very well.

[Peeew]

I have some headlamps from Petzl that are available from outdoor stores that start with dim red light and go to bright red or to white with additional button pushing. For those that like headlamps this can be an option.

[newhaul]

These puck lights were the cure for me for all conditions .
https://www.ebay.com/itm/6-Pack-LED-...edirect=mobile

Instant color change as needed go the situation
Here is a short video I made with the different colors
https://youtu.be/nA_MvAj0q9Q