LED deck or spreader lights

[waterman46]

Originally Posted by Wckoek

Thanks, I am leaning towards spreader lights as well, but I don't see it commonly done, unlike occasionally with deck lights.

Spreader lights or a light on the mast that shines downward to illuminate the deck, seem to be standard equipment on every boat I have sailed on. We just converted our old incandescent spreader lights to LED and the difference is amazing.

[laika]

The underwater stern/swim platform light is something we did makeshift a while back with an old white steaming light waterproofed. We just plug it in to a cigarette socket and drop it in over the cockpit. It's a great addition and I would highly recommend any setup you could make work! Doesn't necessarily have to be as high.gh tech or energy intensive as some of the sportfisher fancy lights you see out there.

[noelex 77]

Originally Posted by StuM

... unless you close one eye or wear an eye patch. Aaaaarhhhh!

This is a great solution and a nice trick to know. The level dark adaptation in one eye does not influence the level of dark adaption in the other. So one eye can be used when studying the chartplotter or radar screen or even making a cup of coffee . If you keep the other eye closed high levels of dark adaptation can be retained in that eye. It is not as good as retaining good night vision in both eyes but it is often the best compromise to process detailed visual information but still retain the ability to see very dull objects.

Most people are more comfortable if they retain night vision in their dominant eye. So this is the one that should be kept closed around light. Google eye dominance if you are not sure which is your dominant eye. If in doubt try both and see which works best. It is also worth practicing this skill. Some people find it hard to close one eye. If you squeeze your eye too tightly shut it takes a while before the vision returns when it is open again. On the other hand if it is not properly closed some night vision will be lost.

Something to practice on those night watches.

Another useful tactic is to have one crew member who checks the chartplotter, radar etc and another crew member who is appointed to preserve the best night vision. This crew member might be responsible for visual information such as spotting crab pots or unlit boats when for example coming into an anchorage.

How do you know if you are a pirate?
You just Aaaaarhhhh

[leftbrainstuff]

I suspect laziness and avoidance of working at height are probably the main driver of decknlights over spreader lights.

[Wckoek]

Thanks for all the discussion, I think a spot light would be overkill for a 36 footer, I might opt for a slightly higher power spreader, since I will use it at anchor or dock so night vision isn't an issue.
A smaller cockpit light via bimini, and might look into how I can work out an underwater light on the foldable swimming platform.

[waterman46]

Originally Posted by a64pilot

Nolex and I disagree on night lighting, I am a Retired Military pilot and I know the US Army spent a lot of money on the last few decades becoming a night fighting force, and all their studies indicate that light color and night vision retention is irrelevant, it’s the intensity, not the color of light that will wash out your visual purple and therefore your night vision, so a very dim white light is no worse or better than a red light.
The “red light” myth if you will came from film developing and before any real testing was done. It wasn’t until after Vietnam that serious studies were conducted.

Film developing theory you propose is interesting, but in my own experience red light is very useful. Red light affects different cells in the retina than does white light. Something about rods versus cones I think.

Most of today's electronics have displays that just destroy night vision even when using a "night display mode" and dimmed to the point of almost being unreadable. I have some red film plastic that I cut to fit over the most annoying of those displays (radar and depthsounder) and these greatly reduce night blindness after looking at the screen, while keeping the displays bright enough to read.

But then, these days we are basically sailing IFR at night anyway with AIS, radar, chartplotters and depthsounders, so who the heck needs to look outside the cockpit anymore?

[Adelie]

Other than A64 I see a lot of anecdotal evidence and arguments from 1st principles that red light harms night vision less. Neither carries much weight.

Anybody have any links to empirecal studies in the last 10yr or so?

[a64pilot]

Rods are scotopic vision, no color, they are night vision.
Cones are day vision, much better acuity and color.

Trick to remember which is which for checkride Time is do you use your rod or cone at night ?

If you like red, more power to you. Do whatever you feel works best for you.

[a64pilot]

Not a study but read this, it explains what I have been trying to say, that is there is no magic color that preserves nigh vision, it’s light intensity that washes out the Rhodopsin or visual purple.
The trigger is that while it’s true your eyes are less sensitive to red light, you have to have so much red light to actually see anything that if anything it’s worse than white light.
It’s light intensity, not color that destroys night adaption.
Light washes out the visual purple, and it takes time for it to build back up, that is what is going on when you walk into a brightly lit area and it takes awhile to see again.

You need Mesocopic vision to see very well, that is you need some cones working to give you decent visual acuity, pure scotopic vision, visual acuity is pretty bad.

Your rods (night vision) are most sensitive to blue green light. For that reason it takes very low levels of blue green light to see decently.

What is true is if the level of light is the same, red light is much more protective, but if you turn blue green down to where it’s just enough to see, it is more protective.

http://www.astromax.org/activities/members/kniffen.htm

[Nicholson58]

Originally Posted by Wckoek

Hello, I am looking for installing lightings to improve visibility and enjoyment of sailing, or chilling at dock at night.
It seemed that there are more people installing LED lights on deck rather on spreaders, practically is there any pro/cons of each?

I am thinking of installing underwater light at stern as well, have anyone done this on their sailboats?

We replaced all IC lights with LED including spreaders. We used Marine beam replacement bulbs for all. Find them on line. They have replacement bulbs and new fixtures. We are very satisfied with these. I have six spreader lights of 800 lumens each, 10 Amps each.

[noelex 77]

Originally Posted by a64pilot

You need Mesocopic vision to see very well, that is you need some cones working to give you decent visual acuity, pure scotopic vision, visual acuity is pretty bad.

This is actually the key.

Scotopic (rod) visual acuity is, as you say is pretty bad. So we must use our cones to read even large numbers. Our cones need much more light than our rods. Our rods are bleached out by white light that is dimmer than our cones need to start functioning.

So how do we see detail such reading our depth instrument with our cones without bleaching out our rods?

The only answer is to use a wavelength of light that can be used by our cones but cannot be seen by our rods.

Guess which wavelength this is . Hint: it’s not blue-green .

[PuttingDoctor]

I installed Caprara2 spreader lights on my Irwin 38 to replace the high amperage draw of the original tractor headlights as original equipment. They are dual switchable white/blue.
On my latest 46’ Irwin I used the West Marine product that does essentially the same at a very reasonable cost.
I love my blue lights when at dock or anchored.

[noelex 77]

For anyone that is thinking about ditching their red light, have a look at a proper scientific study such as this one.

If you want to be able to see any detail such as filling in your log, you will be operating at an illumination level where the time required to dark adapt sufficiently to see a very dim target was in the order of three and half minutes if red light was used and 13 minutes if white light was used.

These are not small differences.

[a64pilot]

The reason for that is that the illumination level was the same, idea being of course compare different wavelengths at the same level.
The difference is that at an illumination level that you can read a book with white light, you can’t see much at all with red, you have to have a much brighter red light to see with, and there goes any theoretical advantage.
You have to believe one of two things, it really is this simple.
1. US Military after using red light only for decades changed to blue / green because they are stupid.
2. They know what they are doing, enough so that just maybe they have done some testing of their own with the Billions of dollars spent on night fighting capability.

There are other considerations, but I don’t want to cloud the water any more.

[Kelkara]

The trouble I have with red light ... is that when looking at a paper chart, the information you most want at night (the lights) is printed in magenta ink ... which becomes almost invisible under a red light.