Whay do so many people still choose red night lighitng?

[lydanynom]

Reading the LED thread I was struck by how many people still use red light, and I was just wondering what the rationale for that choice was since the scientific consensus for decades seems to be that dim white light is far superior for visual acuity and takes only slightly longer to recover night vision than red.

This is compounded by the fact that a great many of the red light solutions out there, LED or otherwise, are radiating at 600nm to 650nm, where you will get all of the drawbacks like no detail vision and central blind spot with very few benefits with regard to preserving night vision. You want nothing shorter than about 700nm if you do go with red night lights.

Considering all of that (and leaving aside the topic of cyan lighting and active light amplification devices) I have always tended toward continuously dimmable white light in environments where I will need to switch between detail-oriented reading or working and using my night vision.

[LinekinBayCD]

My guess is that most people believe that red is the best choice and are not aware that there is another school of thought, me included. Also add into it that a lot of people do not sail at night in general, me included.
Do you have an article or paper on the topic we can read?

[Sixpoint]

I wasn't aware of that either... my military and law enforcement training would suggest contrary to your statements, but I'm always open to new (even if just new to me) schools of thought.

Guess I need to research this further.

Thanks for the tip.

SP

[Sixpoint]

On this topic, found a great article about various types of light and their effects on human vision.

Night Vision - The Red Myth

[dhays]

The problem is that there really is no useful light source that won't destroy our night vision. If we need light to be able to see detail, then we pretty much are going to sacrifice our night vision. On the water at night, even the bit of reflected light from your stern light is going to wipe out your night vision. The rods are incredibly sensitive and are quickly and easily overloaded.

It is true that if you use a dim enough light source of a wavelength shorter than 650nm for a short enough period of time, then you can spare your night vision. The problem is that there are very, very few tasks where you need light that it will provide enough.

Being old doesn't help a bit either.

Dave

Originally Posted by lydanynom

Reading the LED thread I was struck by how many people still use red light, and I was just wondering what the rationale for that choice was since the scientific consensus for decades seems to be that dim white light is far superior for visual acuity and takes only slightly longer to recover night vision than red.

This is compounded by the fact that a great many of the red light solutions out there, LED or otherwise, are radiating at 600nm to 650nm, where you will get all of the drawbacks like no detail vision and central blind spot with very few benefits with regard to preserving night vision. You want nothing shorter than about 700nm if you do go with red night lights.

Considering all of that (and leaving aside the topic of cyan lighting and active light amplification devices) I have always tended toward continuously dimmable white light in environments where I will need to switch between detail-oriented reading or working and using my night vision.

[hellosailor]

"Dim" is a relative and subjective concept, while "red" is less variable from one person to the next. And then again, too many folks have seen too many WW2 movies and "know" that night lighting MUST be red. [sic]

Myths die hard.

Ever heard that carrots are good for your night vision?
Yeah, well, that was intentional disinformation started by the British during WW2, so the Nazis would think all the carrots being fed to the Allied fighter pilots (and they did serve them!) were the reason the Nazi aircraft were being "seen" at night. The real reason was RADAR, new and top secret, and by saying carrots and night vision were the real secret...Disinformation works.

Here it is, 70+ years later and still working.

[lydanynom]

Originally Posted by LinekinBayCD

Do you have an article or paper on the topic we can read?

Nothing I can reference off the top of my head, although googling does come up with some good stuff. That article sixpoint linked a few posts below yours has a ton of references at the end.

I was in high school the first time I had cause to read up on this topic (theater geek, was part of a project to re-rig the catwalks and lighting control systems), and have revisited it for various reasons a few times since then.

[pdqaltair]

Originally Posted by lydanynom

Nothing I can reference off the top of my head, although googling does come up with some good stuff. That article sixpoint linked a few posts below yours has a ton of references at the end.

I was in high school the first time I had cause to read up on this topic (theater geek, was part of a project to re-rig the catwalks and lighting control systems), and have revisited it for various reasons a few times since then.

I can't may my hands on it, but I've read papers that support your claim.

My expereince also supports your claim. I can do more in less time with very dim white light than with bright red light.

But more to the point, is eliminating light sources from the deck and inside the cabin. I cover the cabin door (lexan) with a towel and cover all of the cabin top hatches. I cover instruments when not actually looking at them. Power boaters should be required to get a separate license before they can carry a spot light .

[brak]

It may be a matter of chart contrast. As printed, NOAA charts for example would be more legible under red light than they are under dim white light. That and a definition of "dim white" differs. Is it dim incadescent, which is mostly yellow or dim led which is more "blue"? Few lights are actually white.

Personally, I simply like the appearance of dim red more than any other light under circumstances - it feels "warm" and more pleasant.

[jerryrlitton]

They use red night lighting because they do not use night vision devices.