Night light for chart work

[Tzu]

We have a dim diffused red LED above the table. I find it relatively easy to read anything that isn’t magenta but some of older crew members sometimes struggle. I tend to note down anything important that is in magenta on my passage plan notes.

I do have a head torch that has a red light if I want a little brighter but I use it sparingly and make sure it’s off before heading back to the cockpit. Biggest risk to night vision on one of the board I regularly sail is the light in the heads. The switch is just where you might lean if on starboard tack and there’s a window out to the cockpit.

Tzu has both red and LED's in the main Cabin, switchable for red with night sailing. The heads will be getting a (dim) extension of the reds when i get round to re-fitting the lining in there later this year. The dim red light will then always be on with a dim red light when the saloon reds are on.

Made this plan when I realised a quick visit to the loo could temporarily put paid to some carefully developed night vision. And closing one eye on such a visit will put paid to any carefully developed aim.

 

[Pye_End]

I have a cheap, battery, press to turn on cupboard light, liberally covered in green nail varnish. The green works far better than the red for charts - traffic lanes are virtually impossible with red. Just keep plying on the nail varnish till it is dim enough.

There is a similar red one above the sink for washing up and cooking. Nice and dim and also works well.

 

[lpdsn]

I have both.

Under the side deck above my chart table is a strip of red LEDs and a strip of white LEDs. They're fed by a dimmer circuit and a changeover switch, so I can select red or white and the preferred brightness. At night I will set these ones to a very dim red, to make the general area of the chart table visible.

Then, under a wooden lip just above the surface of the table, which hides the clamps that hold the chart in place over the Yeoman, there is a strip of white LEDs angled to spread light across the face of the chart but not shed any upwards. These are on a separate dimmer, and they put just enough white light onto the chart itself so as not to hide red and orange features.

Finally, the chart table light panel has a master on-off switch that is bigger than all the others and placed against the woodwork so that your hand is naturally guided onto it in the dark. This lets you set the dimmer knobs and red/white switch as required, and then easily flick the whole lot off as you stand up and on as you sit down.

Some people would probably say I overengineered it

Pete

That's better than mine. I fitted red LEDs (strip plus truck side lights) around the chart table. They illuminate the chart but aren't directly visible - the chart table is on the centre line so it took a bit of careful engineering (I thought) to ensure they weren't visible in the cockpit.

But, I also did the same in the galley - so can turn on one set of reds to check the chart and turn on the other to make a sandwich and a cup of tea. One even shines right down into the fridge when the lid is open. Got to be careful what you're putting in the sandwich though when you're only viewing the contents of the fridge with a dim red light.

I nickname them the "project manager" lights as they make red things appear amber.

 

[Topcat47]

I have a short strip of red LEDs of the sort used to remark the long sides of artic trailers. It runs off 12 volts and works for me.

I got them from Furneaux Riddle in Portsmouth.

 

[PetiteFleur]

I also fitted a red led several years ago but have added a 24v standard bulb running on 12v so very dim, and of course will keep going for a long time.

 

[LittleSister]

I've read, on several occasions, persuasive arguments that the idea that red is better a preserving your night vision is a myth. Old wives tales and tradition keeps the red chart light market going, it seems.

My previous boat had a very nice chart lamp with a gentle, directional red light on a long-ish flexible stem. It did create a lovely ambience in the cabin at night when aimed at the cabin head and sides, but not so good for reading charts printed in the last 50 years.

I have become convinced that a (warm) white lamp (I haven't found better than ye olde incandescent for this job) illuminates better, and can be dimmer than a red one for either reading charts, or for illuminating the cabin just sufficiently to allow safe moving around at night.

 

[[70521]]

Isn't it easier just to turn the brightness of the laptop screen down?

What if you don't have one onboard?

 

[LittleSister]

Isn't it easier just to turn the brightness of the laptop screen down?

What if you don't have one onboard?

You ring someone ashore to turn it down for you.

 

[Graham376]

We used to do a lot of night sailing so fitted Hella red led night lights throughout the boat. Only problem is as mentioned above, detail on charts is very hard to see so I use small white flexible light for chart work. I've found the worst killer of night vision is using a tablet for reading, even with brightness turned reasonably low.

 

[alan_d]

I've read, on several occasions, persuasive arguments that the idea that red is better a preserving your night vision is a myth. Old wives tales and tradition keeps the red chart light market going, it seems.

This is correct. When the retina is fully dark-adapted it is the rod cells only that are stimulated by the incoming photons, and they are essentially monochromatic. If you are seeing colours at all you are not maximally dark-adapted. The dark-adapted eye will perceive even coloured lights as light grey provided that are they are sufficiently dim/distant not to ruin night vision.

 

[MM5AHO]

I read some research on this last year. It's all about rods and cones in the eye, but the only useful bit I remember is that green is better than red for this night vision application.