LED Lighting - Chart Table?

Jonny_H

Jonny_H

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I have just made a new instrument panel for the chart table to take the new plotter / DSC VHF and was just about to remount the light (you know the type - long flexible neck with a red cover for the filament bulb) when I spotted red LED lights in Halfords designed for boy racer cars.

This then got me thinking - has anyone tried using red LED's at the chart table instead of a standard light? Are they bright enough / too bright?

I found these lights on ebay:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?V...p;rd=1&rd=1

They look like they could do the job well. Also, as they are waterproof - they could be applied to other applications (night reading lights in the cockpit?)

Anyone used anything like this? Any thoughts?

Thanks

Jonny
 
I've just looked at the website and you may like to check if they ship to the UK. They have left it off the list but I can't see any reason why that would be a problem.
Allan
 
Previous postings have indicated that colours on a range of printed material may fail to show up correctly.

I hesitate to install one of the kitcar leds without testing it against a variety of printed material first. They should also have an internal voltage regulator to prevent premature burnout.
 
Re: LED\'s: Some general info

LED's work at a specific voltage ~1.8 to 3.8V. Their brightness is current controlled. They tend to have specific beam angles which can be between 8 degrees and say 22 degrees. There are a number of suppliers on the web who don't tell you how to connect LED's into a lighting system. There are a number of suppliers on the web who fail to say how their LED bulb which fits into a standard marine-type light performs in terms of brightness and quality of color.

So many questions and not many answers .... Caveat emptor!

LEDs, IMO, are the way forward and will take over from both incandescent and fluorescent (re luminous efficiency) within the next 18 months, but at present they and their electronic drivers that make them work are still in their infancy ie a single 5W white 80 lumen 120 degree warm white (Luxeon or similar) LED can cost (wholesale) upto UKL 21.00 ..... and if you get the voltage or current wrong then it's €€€€€€$$$$$$$$$$$$plhalttttt!

BTW, LED's emit light at specific wavelengths - If you have a nightime red LED at the chart table then you are not going to be able to see anything on the chart where the ink does not contain red .... so ~80-95% limited greens; ~65-100% limited blues; etc depending on the LED ....

There's a simple LED experiment that you can do if you have say a tricolor lens: Take a red LED and shine it through the white green and red portions of the lens -- I dentify what happens and if you have a lightmeter then the results will just confirm that your eyes haven't gone funny.

The best test is to suck it and see ... Don't waste your money on something that won't work for you unless you know how to build/incorporate the next generation of intelligent LED driver .....
 
Re: LED\'s: Some general info

I'm gonna try a Laptop LED light ... runs off 3 rechargeable AA batteries ... just colour the lens red ... and it it don't work, then wipe the lens clean!
If it does work then I can look at doing a perm install.
 
Another cheap alternative is the garden deck lighting kit from Screwfix. This has a rather blue light with several LEDs. You get four lights, connectiong cables and a 12 v supply that works off mains power which you don't need.
I've fitted one into a cabin light fitting. It's OK for general illumination but a bit weak for reading at a range of about 2 feet.
Cost - if I remember correctly was about 22 quid a pack.
 
Thanks for the PM. I have looked at sourcing red tempered glass that will fit my existing 12v halogen lights above the chart table and have found a supplier who can supply 2.7mm glass. Also looking at Hella LED units ( they come in red at about £21). They will need to be switched which must be simple to wire in. Not sure how bright they are but think the LED string shown on your link may be too bright.
 
Tried the red neon tubes, also for boy racers? I have one fitted above my nav table and first impressions are encouraging. The type I have are 9" ones from Wilco auto factors, around £8 each. They state that they're extra bright, seem pretty good to me.
 
A quite recent newspaper article by a consultant opthalmologist ( eye-fundi ) pointed to the mistaken 'urban myth' that red light is helpful in sustaining night vision. It doesn't.

It's all to do with rods and cones, and where they are distributed.

The best and professionally-recommended approach - well known to aircrew who have to read charts, instruments, and keep good lookout at the same time - is dimmed warm white light. Sure, some of the instruments are edge-lit in reds and greens. That may have more to do with marketing than physiology.....

That white/dimmed approach works for me, and will for you too.

Let the outrage begin.....

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Herrnit! It's me tired ould eyes, doc.....

But, seriously, folks. Learned many moons ago, while doing airborne astro and plotting 7 miles up in the sky for a living - one-armed paperhanging stuff - that 'Red light bad - white light good'.

Checked this out with the aeromed specialists and they told me 'Well, of course. Doesn't everybody know?'

These days, I use a LED headtorch.....

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I purchased some white LEDs with resistors for 12 v use on ebay from a guy in Honkong.

Soldered resistors to LEDs, then wired 4 together and mounted in the end of a flexible chart table lamp (also bought cheap on ebay, fixed the short circuit first though). Used silicone sealant to hold the leds in place after connecting wires to bulb holders.

This lamp is used in the galley so that light can be directed to where needed and does not shine into cockpit. The 4 leds are probably too bright for chart table used, two or three would probably be OK.

Would suggest low intensity white rather than red for chart table to avoid loosing detail on charts or books.

Have also used red led (as above) to replace compass light but the beam is a bit tight. Illuminates the card by the lubber line OK though and doesn't matter if left on all day with such a low power drain.

Have fun.
 
I have essentially replaced all my lights in my 3 cabins with LEDs, which I bought on Ebay for about £10 including resistors. As posters say there is a variety of light angles, intensity and colour. I usually mix 2 red with 8 white to produce warmer general light. For thing like chart table I would try 7 red and 2 white.
In quanitity they are dirt cheap so the cost of an array of 10 leds is under £1, and at that price you can play and not worry if you dont get it right first time.
 
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