Colour of Light for Best Night Vision

[zeehag]

Originally Posted by Trekka

One advantage I have found to using red in the summer months is that it attracts far less bugs than other colors. And more critters are willing to keep their eyes wide open watching you and thus reveal their presence.

havent found bugs in the deep blue sea as yet.... so that is best for on shore or in a marina. rarely i find bugs in an anchorage , and nearly never at sea--just one misguided bee in gulf of mexico..

[webejammin]

Our cockpit light has both red and white led's in one fixture with a reostat to dim the light to almost nothing and only uses .02 watts.

[zeehag]

i use absolutely zero additional lighting in cockpit on passages--only the nasty white dimmed gps illumination.
my only interior light used in passages is my glow of pale yellow that has a cloth over top to reduce glare to nothing. works perfectly in long passages off shore where there is no ambient light other than stars, moon and darkness of sky--perfect place to be ..

[Bash]

Originally Posted by zeehag

i use absolutely zero additional lighting in cockpit on passages--only the nasty white dimmed gps illumination.
my only interior light used in passages is my glow of pale yellow that has a cloth over top to reduce glare to nothing. works perfectly in long passages off shore where there is no ambient light other than stars, moon and darkness of sky--perfect place to be ..

you might want to consult the owner's manual for your gps. Most nav gear made for the marine market has an option for a night palette.

[David M]

From what I read ages ago, red closes down the pupil less than higher frequency light for the same apparent brightness. Isn't closing down the pupil less for a given amount of brightness what you would want?

[zeehag]

Originally Posted by Bash

you might want to consult the owner's manual for your gps. Most nav gear made for the marine market has an option for a night palette.

is turned down to min...is just a whiter lite than i am used to using.
when i look far out i need to cover it so i can see in darkness better.
is garmin 498.

[perchance]

Night vision goggles. Problem solved.

[Lars_L]

A instrument of any kind, speed, log, deep sounder and even monochrome radar, shall have dimmable red light if they shall be used during night and you want to preserve your night vision. If you want to use instruments were colour are essential, for example chart plotters, do best to dedicate one person (who will ruin its night vision) to do this works.

There were several heavy texts Grod have links to (#8). They say that there are tree types of cons, and those cones that are sensitive for red is the absolutely most common. If red doesn’t close down the pupil as much as other colours, that would also contribute to the favour of red.

As noelex say, rods can’t see details. Do a test by have the frontpage of a newspaper in front of you. Pot the focus beside the paper (more than 15°) and try to read. For my self, I can’t read even the biggest signs. The rods are they who beside focus and are most sensitive to blue-green and can’t see colour. The only time blue-green is usable are in cabin to be able to orientate your self. In my boat, which is quite narrow (2.5 m / 8.3 feet), I have seldom problem with the orientation.

A more serious problem is what colour shall I have on the buoy rescue light (ore similar equipment)? White has all colours and is most used today. But there is limited capacity in the batteries and you want it to light as long as possible. In other words, the light should use as little power as possible. When you have thrown rescue buoy and whit that the lamp, it takes a period of time before you are back to that place. During that time the distance to the light have been quite big and the light have dimmed a lot. Way use the limited power on all colours when you only see the blue-green? Its good if it flashes because the rods are more sensitive to changes, and it saves energy.