Red map light: good idea?

[StarHalo]

Moderator Edit
Please reread the CPF Rules and FAQs, particularly rule #4.

--Alaric D

 

[Echo63]

We're days away from the year 2018. Are we really still trying to read paper maps in the car?

Paper maps, No.
Road books using tulip diagrams, in conjunction with a trip meter - Yes.


I am planning on modifying the wiring on my overhead "map lights" in my subaru, to give a very dim red when the passengers light is switched on, and a normal "warm white" in both sides when the drivers side switch is flipped.

 

[Lynx_Arc]

Personally I think a dimmer "enough" light level works fine instead of red lighting. Sure it can affect your night vision but in a vehicle unless you are driving without headlights in the dark I don't think changing to red lighting would help vs dim white lighting as once you look at stuff with your white headlights you've already compromised whatever night vision you have anyway. I've had red and green lighting on my dash and I have mixed emotions about them both as I like both colors of lighting for different reasons in that red lighting is more relaxing than green which is both good and bad. Green lighting can help keep you awake if you are starting to get too tired than red which can relax you if you need to be relaxed but if relaxed too much you could nod off while driving. I don't really notice any difference in night vision driving with my headlights on between the two colors and when you have a huge contrast in the light in your vehicle and outdoors shining in either in a tunnel or when driving into the sun sometimes a brighter lit dash can be seen easier than dimmer (or red) color. I'm thinking one reason red is used by the military is less for night vision and more for remote detection that is when you run a red light the enemy cannot see it as well at a distance than white light and since pilots usually don't have strong enough "headlights" to see anything while in the air reflecting back on them having night vision is a great advantage.

 

[-Virgil-]

once you look at stuff with your white headlights you've already compromised whatever night vision you have anyway.

Actually, night driving with headlamps (and roadside building/sign lights, street lights, etc) is in a visual mode called "mesopic". It has elements of "photopic" (bright light) and "scotopic" (dark) vision modes.

red lighting is more relaxing than green

Interesting claim. This is your personal opinion you're stating?

Green lighting can help keep you awake if you are starting to get too tired

{{{citation needed}}}

red which can relax you if you need to be relaxed but if relaxed too much you could nod off while driving.

{{{citation needed}}}

I'm thinking one reason red is used by the military is less for night vision and more for remote detection that is when you run a red light the enemy cannot see it as well at a distance

This sounds like a guess, right? Because {{{citation needed}}}.

 

[Daniel_sk]

It's very difficult to read ordinary maps under red light - that is because anything printed in red color will become almost invisible on paper under red light. I think the older military paper maps actually omitted red because of this, it's also difficult to distinguish colors (again - that's an issue with maps, when you have different trails marked with different colors). This is from my experience while night hiking and trying to use red light. I prefer low lumen warm white color for this use case.

 

[Lynx_Arc]

Actually, night driving with headlamps (and roadside building/sign lights, street lights, etc) is in a visual mode called "mesopic". It has elements of "photopic" (bright light) and "scotopic" (dark) vision modes.

Out of town when headlights aren't hitting anything but at greater distances the light reflected back shouldn't affect night vision anywhere near as much as when you are in town driving.

As for Red vs green being more relaxing it is sort of why people want warm white LEDs vs puke green tints the green tint is more irritating to some (including me).
Finally here is an article that states Red is the least visible color at a distance.
https://sciencing.com/visible-colors-distance-8209029.html

 

[eggsalad]

I was rooting around in my coffee can of random light bulbs (doesn't everybody have one??) and I found a 5w incandescent in amber, so I gave it a shot. I rather like it, and will be ordering an LED version, hopefully none too bright.

 

[Lee Dodge]

Link from the same page;

http://www.madsci.org/posts/archives/1999-10/939051861.Eg.r.html

 

[ssanasisredna]

It is 100% fact. Subs rig for red before going to periscope depth for this reason. Pretty much a well established fact in the military circles.

That doesn't mean that red is "better" for seeing or even necessarily for maintaining night vision. There is a lot of misinformation, misinterpretation, etc. about red-light and night vision.

w.r.t. subs, while where is the concern about not waiting for night vision adaptation, it is also because light goes both ways in a periscope and you want to ensure the least visibility if light accidentally exits the periscope.

If you truly want to maintain your night vision, you must use >660nm as indicated above. This is where the photochromatic step is. Anything less, and mainly you are just using a low effective amount of lumens.

There are some other advantages of red including less glare at low lighting levels, and you have highest visual acuity in the red, if the target has high contrast in red. However, in many cases, and as a general rule, you would be equally served by a very low level of white light which guarantees contrast in far more situations and will still allow you to maintain a level of night vision suitable for driving.

Who the heck uses paper maps any more though?

 

[BVH]

I suspect there's a good reason why general aviation aircraft of numerous brands use red lighting for the instrument panel.

 

[JasonOk]

I suspect there's a good reason why general aviation aircraft of numerous brands use red lighting for the instrument panel.

Might have something to do with ground lighting, air traffic control, what not being anything other than red? Really have no idea on this and totally speculating that i might be right in an attempt to find some truth.

 

[BVH]

It's to preserve the pilots night vision to help him or her to see and avoid other traffic.

 

[JasonOk]

Might have something to do with ground lighting, air traffic control, what not being anything other than red? Really have no idea on this and totally speculating that i might be right in an attempt to find some truth.

Well i'm wrong here as i just remembered/realized that most tower warning lights/beacon lights are in fact red.

Edit: i think there is still alot to be learned here, though we may be at the risk of getting of topic

 

[Alaric Darconville]

This is getting rather off topic. We could go for some time about blue taxiway lights on runways, the various beacon colors and flashing patterns defining the type of airport, and all that.

But this is automotive lighting.

I think this thread has run its course.