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Old 14-08-2012, 06:55   #16
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Re: Red or white at night?

This article has been around a long time: Night Vision - The Red Myth without academic substantiation but seems credible.

This one is based on US Navy studies: Red Light and Night Vision

The Navy study: http://www.dtic.mil/cgi-bin/GetTRDoc...c=GetTRDoc.pdf

My conclusion is that light level is more important than color, and that most people use light levels that are too high for good dark adaptation. From experience on many many deliveries crew often show up with red lights, particularly head lamps, that are way too bright.

At sea, one should have your gear organized so you don't need much if any light to get ready for watch. Black out the head portlight so those coming off watch can use as much light as they like for ablutions before going to sleep.

On my boat, lights below at night are seven or eight red LEDs on the power panel, dim orange from the main VHF, dim orange from the SSB, and a dim blue glow from the panel of the entertainment radio. I don't have any trouble negotiating the boat with that ambient light. In the head, in addition to the main boat lights, I have an inexpensive battery powered LED "closet light" that is bright enough to shave with without the brilliance of the overhead halogen lights.

If you're aboard with me on Auspicious or on delivery and turn to look at me coming up the companionway with a head lamp turned on, regardless of the color of light, I'll be sorely tempted to rip it off your head and heave it over the side. Don't point lights in people's faces.
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Old 14-08-2012, 06:58   #17
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Re: Red or white at night?

Stick with red as it less influences your night vision.

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Old 14-08-2012, 07:10   #18
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Re: Red or white at night?

problem is--everyones ability to accommodate and see in dark varies and some can use red others cannot use red and will use what does work for them. i find blue-white lights most offensive for keeping night vision--they hurt. i cannot see underr ed light--i use a soft almost yellowish tinged light--a warm 1 watt led i found to use in a special lamp i use while at sea.
never but never shine any kind of light--headlamp or other wise--into anyones face under any circumstance. leave the headlamp in the bunk for reading. or use it to scare off intruders--that works nicely.
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Old 14-08-2012, 07:20   #19
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Re: Red or white at night?

I have a dimming red and white light on my chart table that I set to just barley lite, so I can see the colours in the chart, the interior electronics do in fact provide plenty of ambient lighting inside to safely move around, in the cockpit i have two headlights that has red and white and a super white, i put some duck tape over one which only allows the red to show and the second is hanging along side the chart plotter. I did install some blue courtesy lights but find they can be too bright and need to dim them with a shield of tape and cardboard sometimes. I have a mag light led which is really nice and will last 70 hours and can be dialed from spot to flood, i am trying to make a filter from tail light tape and a canning ring to fit in case i need a power full red spot.
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Old 14-08-2012, 07:20   #20
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Re: Red or white at night?

Yep. As Zee says - beware if you are color blind, etc.. Some folks can't use red at night.

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Old 14-08-2012, 07:21   #21
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Re: Red or white at night?

There's a debate about red vs white light AT NIGHT??

Among whom?? No debate on our boat!
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Old 14-08-2012, 07:35   #22
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Re: Red or white at night?

Quote:
Originally Posted by barnakiel View Post
Yep. As Zee says - beware if you are color blind, etc.. Some folks can't use red at night.

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For most colour defective observers the defect does not effect their ability, or the advantage, of using red light at night.
There is a specific type of colour vision defect where observers have a decreased sensitivity for red light. This is not common, but if fall into this catogory you should be aware of it as there are lots of other implications, such as a higher incidence of running into the back of stopped or braking cars. If you have this (rarish) type of colour vision defect the advantage of red light in preserving night vision is, as Barnakiel says, diminished, or lost.
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Old 14-08-2012, 07:50   #23
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Re: Red or white at night?

Another interesting article: The Eye and Night Vision | American Optometric Association

Really dim white light works best for me.

I'm going to start taking more vitamin A.
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Old 14-08-2012, 18:21   #24
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I have heard (not sure where) that the best night light is an oil or kerosene lantern. This seems to go along with what most people are saying re brightness and colour. Also because it changes the light waves pattern and doesn't stay at one intensity and colour frequency like modern lighting.
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Old 14-08-2012, 18:32   #25
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Re: Red or white at night?

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Originally Posted by Coachbolt61 View Post
I have heard (not sure where) that the best night light is an oil or kerosene lantern. This seems to go along with what most people are saying re brightness and colour. Also because it changes the light waves pattern and doesn't stay at one intensity and colour frequency like modern lighting.
Coacholt.

I'd love to have a kerosene light for the backlight on my autopilot, instead there was a bright blue light........blah!!!
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Old 14-08-2012, 18:46   #26
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You might like to peruse the following if you're interested in the finer details of lighting on ships.

MILITARY HANDBOOK LIGHTING ON NAVAL SHIPS (METRIC) describes the use of red light to protect night vision. (Scotopic vision)

You can download it for free from everyspecdotcom.
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