PetiteFleur
regular
Reged: 29/02/2008
Posts: 224
Loc: Suffolk
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Fitted a red LED light over the chart table in the spring but when used a couple of weeks ago found it was more than useless as I couldn't see the majenta lines or marks at all. As we were crossing the new Sunk precautionary areas at night it was bit disconcerting but ok after I'd switched on the original white fluorescent lamp which I had left in position. What is the forums opinion on the best lamp to use? I was using the Imray C30 chart at he time.
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npf1
regular
Reged: 09/10/2004
Posts: 1145
Loc: Oxfordshire
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I've got both red and white at the nav station - like you, I end up using the white when I need to take a close look at the chart. But I do leave the red on at all other times.
Have often wondered what green would be like, which, I was once told by an RN man, is what some Navy vessels now use.
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Login_name
regular
Reged: 07/05/2008
Posts: 555
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I've got a white LED over mine. Seems OK.
I was under the impression that, these days, the idea that it must be red was a load of tosh and that the intensity is what matters.
Someone will be along shortly to give a definitive answer.
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michael_w
regular
Reged: 08/10/2005
Posts: 2278
Loc: South London
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I think the Aqua Signal (scroll down a bit, they're called Toronto) chart table lights are the dog's whotsits. They dim by using a nifty polarising filter rather than a red shade. Not cheap.
Worst things are those bendy car ones. Complete rubbish as the area of illumination is usually far too small. You have to keep on adjusting the poxy things.
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"Procrastinate now! Don't put it off"
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davies
regular
Reged: 10/01/2007
Posts: 228
Loc: Work in London, live in Portsm...
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The red helps me find the chart table in the first place, but I use white for reading the chart.
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Conachair
regular
Reged: 24/01/2004
Posts: 522
Loc: Canaries
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Found this http://stlplaces.com/night_vision_red_myth/
I nearly always use a LED headtorch with a red filter now at night, for cooking, chartwork etc. Though from that artical the fliter may just help by cutting down the total amount of light.
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sarabande
regular
Reged: 06/05/2005
Posts: 5548
Loc: Thames valley, or up on the mo...
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as posted once or twice previously.
http://stlplaces.com/night_vision_red_myth/
To ensure that you get full colour discrimination on a paper chart, a dimmable WHITE light is the only answer. Reds around the cabin are fine to enable crew to locate themselves and their socks.
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Enlightenment is motor-sailing
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jeanne
regular
Reged: 02/04/2002
Posts: 434
Loc: Sanlucar de Guadiana, Espana
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I have read that there is no magic ´níght vision protection´in the colour red, it is simply that a red bulb will be dimmer than a white one of the same wattage. Fit a lower wattage white one and you have the same illumination power, without the problem of seeing the magenta lines.
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pampas
regular
Reged: 17/07/2003
Posts: 616
Loc: Falmouth
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Managed to get hold of some orange lights,the type for low voltage that are used in alarms for secruity about 2.5" dia base the lense has a frezel effect, one above dist.panel two in center of cabin and one in the elastic band space. 5 Watt feston bulbs instead or the original 10 Watt. Found to be excellent for reading charts and nice and soothing when in the scratcher. Incidently Blue light not very bright is the best colour for night use,most ships use a orange shade, one ship I was on, an experiment was carried out with different colours and shades,the mates agreed that the tinted blue was the most pleaseing but nothing more was heard. I think red was used,probably because red glass was easily produced and all Naval gun decks were red in order to reduce the visual impact of blood to the occupants.
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DogWatch
regular
Reged: 10/09/2004
Posts: 9340
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I use one more like this
But mine has a bulkhead fitting rather than plugging into the 12v socket. I find it gives a very nice spread of light and as I only turn it on when required it does not need to be LED. I think I have 5W festoons. I bought 2 for some reason, I still have the second unopened.
The nice thing is the flexibility, I can twist it away so that it is not in my eyes and as it is such a low wattage bulb does not kill my vision.
I think I originally bought from cpc but have spent 30 minutes searching and this is the best match I have found, if they are discontinued I am glad I bought 2!
I know you mentioned map lights, but this is not the same, the lamp is not coned and so is more alike a car interior light above the seats, if you see what I mean...
the best I found is here. If interested, you may be able to convert to bulkhead, though it may suit to be a 12v socket fitting,..
EDIT>>
found another image, this is the type of lamp head, though the flexi part on mine is quite different..
Edited by DogWatch (02/07/2008 23:00)
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maxi77
regular
Reged: 11/11/2007
Posts: 818
Loc: Kingdom of Fife
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It is now many years since watchkeeping was my day job, but from experience yes red lighting is lower intensity so your irisopens wider making it easier to see in real darkness. I think also you see more clearly with low intensity red light than with low intensity white light. For actual chart work we used lights which had both a dimmer and gradual red filter. All red allowed you to see the chart basics but to see all the detail you did need some white. Some chart symbols are almost invisible in red light.
By the way if you want to have full night vision immediately you need 'black lighting' even if you have been using dim red you do not have full night vision for a minute or so.
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Peter
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RECUSANT2
regular
Reged: 04/04/2006
Posts: 587
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I have both red and white. The red is a 9' neon tube from an auto factors, the sort of thing boy racers stick inside their cars, seems to work ok. Draws 0.3 amp.
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Somewhere in Texas......................................A village is getting it's idiot back.
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Kevin_Mac
regular
Reged: 10/03/2006
Posts: 210
Loc: Poole
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How about just keeping a pair of sunglasses by the chart table, using them at night with ordinary white light?
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jerryat
regular
Reged: 20/03/2004
Posts: 3233
Loc: Nr Plymouth
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Quote:
I think the Aqua Signal (scroll down a bit, they're called Toronto) chart table lights are the dog's whotsits. They dim by using a nifty polarising filter rather than a red shade. Not cheap.
Worst things are those bendy car ones. Complete rubbish as the area of illumination is usually far too small. You have to keep on adjusting the poxy things.
Yep, that's the one we've used on our boats for many years! Really excellent bit of kit. 
Agree with you that the bendy ones are rubbish. 
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geoffatstanpit
regular
Reged: 10/09/2004
Posts: 601
Loc: Christchurch UK
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Doesn't anyone use the old boy scout's trick any more for map reading at night without spoiling your night adaptation? Just shut one eye, turn on the torch, read map, turn off torch. You have one-eye vision for a few minutes but better than nothing and soon gets to be a habit. Very cheap solution to the problem!
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moody1
regular
Reged: 10/12/2005
Posts: 414
Loc: Anywhere in N.Europe / Baltic ...
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Quote:
We use same - in 12v version, but hubby removed the plug and adaptor as they were unreliable. The resulting flexi end was suitable to press into a drilled slot to fix with epoxy. Cable exiting behind and wired up.
We painted the lens apart from flat that directs exact at chart table with red lacquer. That way we have good light on chart, but subdued red around to reduce effect on vision. Hubby bought a handful of these and has plans to fit above bunks as reading lamps.
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Some of us Ladies may surprise you.... Wife of Refueler
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