Night sailing - chart plotter brightness

[carstendenmark]

I am considering to buy a completely new navigation system, but as I've read in several magazines, they all say that the most important for night sailing is the low light ability of the chart plotter and other instruments.

If the main information (exept the compass) at helm is the chart plotter, which ones has the sufficient low light setting for night sailing, to not disturb my night vision ?

I appreciate all inputs :-)

[carstendenmark]

Seems Raymarine fights with implementing this :
https://forum.raymarine.com/showthread.php?tid=5936

[SV DINGO]

My Lowrance has night mode in red with different intensity setting but i hardly ever use it. I use an Android Smsung Tablett with a redfoil for night sailing.

[noelex 77]

It is good to hear you are considering options to preserve night vision. Too many sailors adopt strategies that results in poor night vision.

Unfortunately most of the chartplotters are poor in this regard, although to be fair it is impossible to convey all the detailed information on a chartplotter screen without sacrificing some dark adaptation.

The best strategy to to have instruments that convey vital information such as depth, compass and speed set up with dim red illumination. Simple numbers such as this can be read while still preserving the best night vision. If you need the more detailed information from the radar and chart accept this will reduce your night vision and plan accordingly.

A useful strategy is sometimes to use just one eye when using these instruments or even better have one crew member who preserves their best night vision by not using the chartplotter.

[tkeithlu]

The dimming does not have to be red as long as the light level is so low that it does not bleach your rod (night) vision receptors. That's pretty dim, but a level you are aware of from moving about in your house or boat at night with some bits and pieces of lighting. We use rectangles of ordinary automobile window tint plastic sheet over the radar and the nav monitor.

[Sailmonkey]

Our raymarine axiom has night mode, it sort of works, the color palette changes, but the underlying brightness is still there.

Our solution is a swing arm, the plotter swings into the cabin. So unless you’re navigating tight coastal waters (narrow channels etc...) the plotter remains on yet not disturbing the watch stander and can be swung out in seconds if needed.

[carstendenmark]

Thanks, noelex
But, no help from crew members, as I mostly sail singlehanded.

My cellphone Samsung S9 can dim the light when I use the local charts. Of course that's an OLED screen, so it should be able to turn completely dark.

But it seems that the chartplotters has forgotten this issue ?

I may grow a ponytail, show a pirate flag, and get me an eyepatch for the night vision.

But that does not help much when the fog sets in.
And it does so, mostly in the late autumn here...

[carstendenmark]

tkeithlu, that was a good one, thanks !!!
However, would be nice, if the super expensive marine devices already had a feature of dimming from bright to zero.

[pjShap]

My Garmin plotter lets you adjust the backlight percentage, down to 5% of full light, which is too dim for me to read anything. Works well for me at night. As someone said, reading the plotter detail might require more light than you would ideally want for night vision, but if you need the plotter you have to see the content.

[noelex 77]

Originally Posted by tkeithlu

The dimming does not have to be red as long as the light level is so low that it does not bleach your rod (night) vision receptors. That's pretty dim, but a level you are aware of from moving about in your house or boat at night with some bits and pieces of lighting. We use rectangles of ordinary automobile window tint plastic sheet over the radar and the nav monitor.

Rods do not have enough resolution to see numbers (such as the depth reading) unless the numbers are impractically large.

In simple terms to read numbers you must use your cone receptors. Unfortunately cones are much less sensitive than rods, so any white light that enables you to use your cones and read numbers will bleach out your rod receptors.

The exception is far red illumination. Rods are very insensitive to this wavelength. They cannot respond to red light so dark adaptation of the rods is preserved or largely preserved. As rod adaptation takes around 20 mins to establish it is a useful trick.

To see detailed information such as on a charplotter monochromatic dull red illumination is difficult. If you need to study the chart it is sometimes better to accept the bleaching of your rod receptors and use dull white illumination, but occasionally if minimal information is needed dull red can still be better. It depends on the circumstances.

[carstendenmark]

I think some experiments has been made with green and blue low dimmed instrument lights.

We might need some pros with proper experience.
Any submariner's or navy's around ?

[Ded reckoner]

We've done almost all short hops up the US East Coast with night passages (so we have light leaving and entering inlets). We have Garmin 1022Xsv chartplotters which lower light levels automatically with dusk. Our experience with these are good for nighttime use for navaids, obstructions, shoaling, radar, and AIS. Of course, we supplement chartplotter use with periodic visual scanning outdoors (we have a pilothouse sailboat, but the house rule is to go outdoors and look around). Our impression is that we're unimpaired doing visual scanning with chartplotter use. I think a good practice would be to do the visual scanning first and then study the chartplotter.

[StuM]

Originally Posted by noelex 77

A useful strategy is sometimes to use just one eye when using these instruments

[StuM]

Originally Posted by carstendenmark

I think some experiments has been made with green and blue low dimmed instrument lights.

We might need some pros with proper experience.
Any submariner's or navy's around ?

There have been a few very long threads discussing this with a great deal of biology, chemistry and physics explanations as well as good feedback from experienced servicepeople with night operations experience (including helicopter flying). Here's three to get you started

https://www.cruisersforum.com/forums...ion-67713.html
https://www.cruisersforum.com/forums...on-209780.html
https://www.cruisersforum.com/forums...th-233283.html

[carstendenmark]

Thanks a lot, Stu
Good for my bedtime reading !

Frankly, I didn't knew about that...
CF is SOOOO big !

Bottom line, the chartplotters should now (2021) be made to facilitate reading in very low light conditions for night sailors.
My phone can do it, but not a 3000$ chartplotter.

Thanks for all replies !
Still, anyone here know of a good one ?