LED Bulbs in navlights

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ditchcrawler

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I was looking at using an LED bulb in my Aqua Signal Combined Port/Starboard light on the bow,but one of the websites says that you need to use a green or red or white LED,and that you cannot use a white in a red or a green light( or a combined) as a white LED through a coloured lens gives the wrong colour.
Chandlers are selling white LEDs as a straight replacement with no mention of this possible problem.
Anyone know if this is true or just relates to one manufacturer.The website I looked at was www.searolf.com
 
The problem is that LEDs are specific colours. The red and green ones are very efficient. The white ones work by using a phosphor which absorbs the blue or uv produced by the LED and re-emit it as a broad band of colours which add up to white, thereby reducing their efficency (due to the phosphor not being 100% efficient). Therefore, if you put a white one as a straight replacement for a tungsten bulb, you throw away even more efficiency because you reject the colours which are not transmitted by the filter. In addition, the filter is designed to take the spectrum of a Tungsten filament bulb and transmit the colours that you want, ending up with a red/grren light of the right colour. If you start with the rather different spectrum from the LED/phosphor, the balance can be wrong so that you end up with the wrong colour (blueish, rather than green has been reported, for example). Some manufactueres may have tuned the phosphor on their LEDs accordingly (or may be ignoring the problem).

To get all the advantages of LEDs, you should use the coloured LEDs. They are brilliant in all senses of the word! However, that does mean a substantial outlay in replacing the whole fitting rather than just the bulb.

They are bound to become cheaper, probably very soon, because the components are incredibly cheap and it's just the manufacture of marine-specific fittings (in relatively low quantity) which is why they are expensive now. It is still a very young technology - the first blue and white LEDs were only invented a decade or so ago.
 
Ultraleds are doing a warm coloured bulb. I guess that imitates the colour of tungsten light thus solving the 'blue starboard' problem.
 
Hmmm, we bought a warm white Ultra led's bulb last year and used it in our aqua signal tricolour. I'm not impressed with it, yes you can see the coloured segments but its not nearly as bright as the tungsten bulb it replaces in the red and green segments when viewd from another boat. I'm going back to the origonal bulb unless I can find a genuine replacement led to shine brighltly thorough the red and green.
 
ditchcrawler, out of interest, why are you looking for an LED for your bow light? Surely you'll have the engine running when that one's on? I bought a coloured LED 'cluster bulb' for the masthead tricolour from doctorled.com as well as an all round white anchor light. Both seem pretty bright although for now I've gone back to a halogen in the tricolour (can’t say why, I just feel happier with the halogen back in). We have a good wind genny (D400) and if there's enough wind to sail there'll be enough power going in that I don’t worry about the halogen tricolour. If I was doing an Atlantic crossing then I might go back to the LED but for the occasional night sails I do (usually followed by a day on shore power in a marina!) the halogen is just fine. Hence I'm only actually using LED's in the anchor light. That does use an impressively small amount of juice though and I’ve no ambition to change that back.
 
In the Netherlands a big debate is going on about led's replacing bulbs in a tricolor. Someone has worked out that due to the way the led's are arranged, you can never get a clear definition between the green, red and white sectors. A fuzzy zone exists of more than 10 degrees, thus creating all sorts of ambiguous situations.
The conclusion seems to be that led's will only be ok in purpose-designed housings, like Lopolight et al. In that case, I'll wait till the prices come down.
 
While not an expert I am inclined to agree. As someone else said replacing lower lights is pointless as the engine should be running. This leaves the tricolour at the top of the mast. Frankly thats only one bulb and I prefer to be seen. I have yet to be convinced that an LED can produce enough light to replace a tungsten. If you can't run one masthead light for 8 hours you need a bigger battery! Replace your chart table and cabin lights with LED's. Even the anchor light if you must, but leave the nav lights safe.
 
In reply I often prefer to use the lower nav lights than the tricolour at the masthead when sailing, but there are many other power demands i.e.plotter instruments,repeaters,radar,Yeoman for instance.I do have 220 amp hours domestic available (although half this in reality) so I will stay with my standard nav lights.I have just bought new nav lights(I only wanted to replace the lenses but it was cheaper to buy new complete ones) & cosidered the complete LED ones but they are an arm & a leg at present.
Many thanks for all the input & advice.
 
I think Westhinder is right. A tricolour mast head light gets its segments fairly accurately because the bulb has a vertical filament. The filament is fine and the angle from the filament to the change from one colour lens to the next is very precise. As required by the col regs.
Now the LED replacement bulb on the last Oz site might appear to be OK as it is in the form of a column of lights. But because the lights are in a column about 1 inch in diameter there must be a very indistinct transition from white to red to green.
So this bulb will be fine for anchor light or even steaming light but as a triclour replacement I would not be so confident.
Further often LEDs gain much of their brightness from focusing the light in a narrow beam. So a focussed light going out horizontally like a light house is great until the boat heels over, you may find that the nav lights are very dim at 30 degrees. from horizontal.
I would like to know if purpose built LED nav lights are suitable for 30 degrees of heel or are they only suitable for Mobos.
Certainly the purpose built red and green nav lights look great at night. olewill
 
This is more of a general comment than a specific reply to anyone, but it seems to me that the general approach to replacing bulbs with LEDs is to achieve the same brightness at much reduced power.

This is akin to saying "I do not want to be seen any better than the absolute minimum legal requirement."

Wouldn't it be a better approach to use the same power (or even less power than bulbs), but make the nav lights BRIGHTER than they were before? I.E. don't save power - make your boat more visible for the same power.

Or have I got it totally wrong?
 
Brightness is not the only point in considering visibility. Another factor is the size (or apparent area) of the source. At a distance, a very small source may be invisible, even if very bright. That is why nav lights are quite large, with a lens that ensures that the diverging beam is spread form an area of several square inches, rather than from the almost point (or line) source of the filament. The same is true of those solar garden lights that some people (including me) use as anchor lights. I first saw one in use in Dallens Bay and was impressed. They are not very "bright", but in very dark conditions are visible from about a mile. The naked LED would have greater brightness (in physical terms) but would be less visible to the eye at a distance.
 
There are of varying priorities here which mainly divide between 1) Those boats with plenty of electrical supply aboard 2) Those for whom electrical capacity is rationed.

I'm right at the bottom end of the second category with a 80 AH leisure battery and a small solar panel..and thats it. Being a 6m yacht sailed only inland up to now, I only have a masthead white...and nothing else. Frankly I don't ever intend putting to sea in the dark with that setup, legal or not, so the advent of low consumption LED nav lights seems like a godsend to me.

I'd absolutely agree that if you can go to brighter LEDS than the minimum, then do it. I have sailed at night in the Solent and the better lit your are, the safer it is. Not a difficult one that really.

LEDs seem to be the way forward, though the replacement bulbs seem to be a disappointment. I am holding back if only to see what happens to price, and because the rate of development is very rapid at present. I don't think prices will fall that much as LED Nav lights have "Premium Product" stamped all over them, but I can see the market for conventional lights for small vessels shrinking very quickly.

I have to decide whether to go for a masthead tricolour, or for deck level (on the pulpit most likely). I'm not in a rush, and it won't be this year..probably!! I'm not a confident electrician, but as both my neighbours are sparkies I shall do my weak and helpless act on them when the time comes.

Going slightly off topic..did I read somewhere that lighthouses now use a 35watt bulb...amazing if true!!

Tim
 
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