Compass backlighting

[wags on the water]

Has anyone changed the backlighting on their compass for easier viewing at night? The lighting on my Plastimo is red and difficult to view at night.

Cheers,
Wags

[peterbo3]

Hi Wags,
My Ritchie is green. You should be able to fit a green globe or led without too much drama. Go to the Plastimo site for an exploded view.

[wags on the water]

Thanks Peter. I had a stand down day today so had a few hours researching compasses and tying rigs. I've sent Plastimo an email and hoping they can answer the tough questions too.

Cheers,
Wags

[gofishin]

Wags, for years red-orange has probably been the most popular for instrumentation as night vision is normally least effected ‘overall’ by red hues. However, greens have also become popular and there are cases for different colours. Science has come a long way (while my memory is fading , and lot of testing has been done. The intensity and wavelength is probably more important, though not sure how many ‘general/public’ instrumentation suppliers get to this level. It also seems it depends on the individual’s eye to some extent, so choose what you find is best.

My compass light is red, however I put a switch in the ignition circuit so that its only on when I want it on.

If you want to really get into it there is a mountain of info on the net… but it can do your head in .
Cheers
Brendon

“If you need to see directly in front of you or see detail you need red. Like many myths the red light myth has some basis in fact. The red truth?
Why red? The center 1.5% of your retina (the fovea) which provides you with most detailed vision is packed almost exclusively with red sensitive cones.
This is the same area that has no rods and is responsible for the night blind spot. There are fewer total green sensitive cones than red. The number of blue sensitive cones is very small compared to green and red.
Which is just as well since the lens in the human eye cannot focus red and blue at the same time. And using green really only changes perceived brightness because of the way the signals are processed in our neural pathways. Unlike a digital camera, more pixels, in this case, doesn't give us more detail.
……
The key then is finding a hue that we can have at a high enough intensity that we can see the detail we need without activating our rods to the point were they obscure that detail. Most source say this should be nothing shorter than 650nm. Experimentation shows a L.E.D. with a peek around 700nm seems to work best (perceived as a deep red). Note that red may be fatiguing to the eyes.
Conclusions:
· No matter what your color choice it must be fully adjustable for intensity.
· If you need the fastest dark adaptation recovery and can adjust to the limitations, or everyone in your group is using night vision equipment then blue-green.
· If you must see detail (reading a star chart, or instrument settings) and can lose peripheral vision (see note 1), then a very long wavelength red at a very low level. Red really only has an advantage at very low levels (were the night blind spot is very obvious).
…
Note: The red filtered light at the intensity most people use is likely decreasing night vision much more than a properly dimmed white or blue-green light would!

[johncar]

Mine is Red also but it seems to be just right for me, it is very dull and only just enough to make out the heading which seems perfect. I don't want any light pollution from it up onto the windscreen. Headed out this morning early in the black and was thinking how good the backlight was but yeah it is not bright at all, barely glows.

[wags on the water]

Thanks for the replies. My GPS/sounder sits in the middle of the dash and not the best position to be viewing the gps when trying to watch the water and the screen at the same time to stay on course when travelling at night. The red back lighting was too hard to focus on, so I'm wanting to change to a lighter colour - thinking of a lite blueish light. Auto pilot would fix everything but also about $2000 dearer than a globe.

Cheers,
Wags

[cormorant]

Most of the bigger ones had 2 bulbs them and were set up for either 12 or 24 v depending on how you wire the shunt. if shunted for 24v ( Bulbs in series) and only running 12 you will get a very dull glow. It used to be in the install instructions how to do it maybe it was only in the 24v ones?

I have found the plastimo lighting really good in the large ones offshore sailing .
Not sure about plastimo but other brands had a place to put a reflector behing bulb for more light or had the reflector built into the hood / body and a twist one way would dim / brighten and some had 2 places / options to place globes. . Some UK ones have different card colours and light combinations. I think I have greenish card numbers and redlight. Mate who is some sort of partial colour blind can see it at night but not day very well. Not colour blind?
A simpler solution may be to dim the gps even more ( some have 2 colour options for backlighting- all one colour of red may make it easier the eyes) or cover with black cloth like we do as it is always too bright compared to other guages which we cover most except for a small area . Used to let the deckie turn the GPS to face him and I would use the compass to protect my vision but I can't do that with mount on my boat now.

[wags on the water]

Nope not colour blind - checked every 2 years for work. I've had the brightness on the GPS as low as possible and still can't quite read the compass. I guess I'll have to grin and bare it untill something new comes along.

[Lucky 1]

I just bought an Plastimo offshore 75, The led light broke soon after I installed it. To replace it I purchased a red LED light from Jay car for about $2. It just clipped into place(and had to be resoldered.) I can now read the numbers better on the compass, however I have noticed a red reflection on the windscreen, Yet to test it on the field.

[finga]

Hey WAG's. Have you looked at the bulb in question?
Is it a red bulb or a red sleeve on a normal bulb?
A change the colour of a lot of bulbs by simply placing the appropriate coloured translucent sleeve on the bulb.
My old Beemer bike has green sleeves and the dash did not reflect on the screen at all.
Really easy to see too.

Or go the LED path. They're cheaper then SAO's if you shop around. You could get one of each and experiment.
http://www.superbrightleds.com/cgi-b...nstrument.html

Or I have got stuff off this mob and they're good to deal with
http://www.besthongkong.com/automotive-led/

You'll need a light with the widest viewing angle or one with inverted lens sort of set-up to get the most diffused light (no bright spots)

Cheers Alfred

[cormorant]

Forgot about that as well Alfred.

Also with some of the little halogen bulbs they don't use the sleeves but instead dip them in a coloured translucent paint. Bit of acetone rubs it off and they are brighter and a white light. If it it maybe wipe one sideeonly and see how bright it is.

Beer with matetoday and he said there was plastimo 105? I think that were dull as and he had returned his to teh shop.p. Might be worth talking to plastimo if they had a batch with crap bulbs or design? . He also confirmed that some have 2 bulbs in the older ones and commmercial ones as a safety measure and for 24v systems. Not sure about if the new ones are led.


Wonder why they don't have luminescent letters like the old one on the family cruiser? Probably we are being irradiated by it!!

[wags on the water]

Hey WAG's.
Cheers Alfred

Hey Alfred - my name is Wags.

[wags on the water]

Scotty I look at the bulb everytime I turn the lights on in the boat at night - but it is a little bit hard to view it from where I am at the moment. This is one of those projects I should've done after the big trip last year but never got around to it. I definately get on to it in the next month or so. I wish I had more time to tinker with it before heading off on the big adventure this year. Jump off plane tuesday afternoon, load up car and boat, leave home early wednesday morning for the trip north for a week.