Red Mode / Night Mode on iPad

[a64pilot]

Originally Posted by tomdidit

I agree heartily. Your I-Pad lesson makes you the man. The quick thread drift was a little more scientific than I would have preferred and must come from those that are not using I-Pads. Thanks, and let your wife know there are a few of us that really appreciate it.

No, I use an IPad Pro and a regular IPad, just wanted to point out that turning the light level down low is as effective as making it red, without the issues of the red color

[KP44]

Originally Posted by noelex 77

It is a complicated subject. If you want the best night vision and electronic information is of secondary importance, then red illumination is the only option. This is why WW2 planes had red instrument lighting.

If you want a large amount of complex information that can be processed quickly, you cannot do this and maintain the best night vision so dim white light is the best option.

There is a yes and a no to this.
The rods are used mostly when we are adjusted to darkness. The cones see color and the rods hardly even see the longer wavelengths like red light. The rods pick up wavelengths that would be seen as bluegreen in daylight. Using very dim white or green allows us to see at a far lower threshold of light. Using red light, we need enough light to allow the cones to pick up the red.

So red will not affect the rods but will affect our slow-phase adaption to darkness (which takes about 45 minutes). There is also a transient adaption effect which takes only about 1 second.
Very dim green or white light will allow the rods to work at night vision levels, below what the cones can pick up. But this is not suitable for most reading or plotting.

So red might be better for some things. But very dim white might be better for walking around belowdecks without losing your night vision.

I have removed all our red lights and use very dim warm white.

[StuM]

Originally Posted by KP44

So red might be better for some things. But very dim white might be better for walking around belowdecks without losing your night vision.
I have removed all our red lights and use very dim warm white.

I often use a cheap USB gooseneck LED reading light in the saloon/galley area when sailing at night. I can vary the brightness by where I place it and where I point it. Or even by hanging something translucent over it.

[Auspicious]

Originally Posted by noelex 77

On a yacht there is also the requirement to do quite simple visual tasks (such as making a cup of coffee or getting dressed). This can be done with minimal visual acuity and for this a dull red light is ideal.

Many people simply want an easy way out and give up their night vision as a result.

If you pack your duffle in daylight with your gear in the order you will put it on for your night watch you can dress in complete darkness. That takes another five minutes so many crew use headlamps and torches despite strong guidance to the contrary. You do have watch bags, right?

Ambient light levels from LED indicators on electrical panels and other sources are plenty for moving around the cabin. With some organization and discipline you can make a hot drink and grab snacks without supplemental lighting.

Night vision is a resource that deserves to be conserved. Light of any color should be at an absolute minimum. It is clear from my experience with many delivery crews that my definition of "minimum" is different than others.

Originally Posted by KP44

I have removed all our red lights and use very dim warm white.

Bravo.

[noelex 77]

Originally Posted by StuM

Or an eye patch over one eye.

Back in the day, I always closed one eye when I needed to use a torch to look at a map or whatever at night, I still do it at times when I go below at night for some reason.

Yes, a patch, or simply closing an eye, is a good solution. All the adaptation is retinal not cortical so if you block the light the eye will retain the benefit. Try to block your dominant eye.

The other alternative is to assign one crew member to monitor the electronics, chart plotter and radar, while another crew member retains good night vision. As dark adaptation takes a long time this needs to done well before, and needs some discipline. A quick glance at an instrument with white illumination means it will be perhaps 15 mins before full dark adaptation is regained (assuming it is a dark night and full scotopic dark adaption is beneficial, which is not always the case).

[kloebereng]

Noting the issue below re: "reverse" on the iPhone, on my 6S I switched TINT and "reverse" ON, and then adjusted the TINT HUE -- I can get a "dirty RED," but not a PURE RED, BUT it has reversed (white) text (only tried it on email apps.)

Ken K

Originally Posted by DaveWaltersAus

Maybe I'm a "gumbie" and this is old news to old salts but I've been trying to do this for two years.

I was gonna buy some red cellophane to put over my iPad when I stumbled across a link solving all my problems with a higher tech solution.

On my iPad I went to
Settings, General, Accessability, Display Accommodations, Colour Filters, (turn them on) , Colour Tint - then slide intensity to max.

Voila - red iPad display. But wait, there's more.

Go back one screen and by reducing "White Point" by 100% you can make the display much dimmer than normal dimming.

Further good news,

Go back to Accessibility main screen and scroll to the bottom to select "Accessability Shortcut". Tick (check) the boxes for "Invert Colours", "Colour Filters" and "White Point".

You're done. If you're in Navionics or your preferred app, you can now "Triple Click" the home button to bring up these options quickly.
"Colour Filters" makes it red
"Reduce White Point" makes it super dim
"Invert Colours" switches the white chart background to black. Nice.

Sadly the "Invert Colours" thing only works on my iPad. On my iPhone it's no longer red but that's ok - it's awesome on the iPad!

My wife is laughing at me because I think it's so cool - I had to tell someone who might appreciate it so I finally signed up on this forum! I hope it helps!!