Red cockpit lights

[Decent Weasel]

So one of the things that stood out to me from the film 2001 was that every ship, or nearly every ship, had red lighting in the cockpit area, sort of like a darkroom (or, more accurately, an aircraft carrier at night). The idea was that this would preserve the crew's low-light vision, letting them track small or faint objects by eye more effectively.

I always thought this looked really cool and distinctive, but ...based on what I've seen of actual spacecraft, this doesn't really seem to be a thing. Is radar so much more effective that tracking by eye isn't worth the trouble? Or is space so empty that you don't really need a naked-eye capability to track other objects to begin with?

Thanks, I know this is probably a facepalm question.

[peadar1987]

So one of the things that stood out to me from the film 2001 was that every ship, or nearly every ship, had red lighting in the cockpit area, sort of like a darkroom (or, more accurately, an aircraft carrier at night). The idea was that this would preserve the crew's low-light vision, letting them track small or faint objects by eye more effectively.

I always thought this looked really cool and distinctive, but ...based on what I've seen of actual spacecraft, this doesn't really seem to be a thing. Is radar so much more effective that tracking by eye isn't worth the trouble? Or is space so empty that you don't really need a naked-eye capability to track other objects to begin with?

Thanks, I know this is probably a facepalm question.

I'd say you're right, optical tracking isn't used often enough to justify using red lights.

However, I know it's used on ocean-going vessels quite a lot, especially racing yachts, where radar can't pick up a lot of semi-submerged objects, and you have to rely on a lookout.

[vger]

Ehh, what about docking?

[B787_300]

even with docking red lights are practically useless. most docking/berthing is done with computers and radar

[cantab]

If you want to orient yourself by sighting the stars, you only need the bright ones. If you're looking at a planet or moon, if it's near enough to see detail without needing a telescope it's bright enough to see easily. Even if you're looking at another ship, if it's near enough to matter then again it's probably plenty bright enough - the ISS from Earth is about the brightest thing in the sky after the Moon when it passes over at night - or else it's in shadow and too dim to see anyway.

Basically you won't be looking at faint stuff for flying a spacecraft.

[WestAir]

I've been told that green lights are just as effective as the red ones in preserving night-vision.

While I'm not sure about space travel, in the aviation field a lot of newer aircraft have green or orange instrument panel lights to keep night vision sharp. In my opinion, the pictures suggest they blend in with or mimic street lighting from above.

[Seret]

We used to use red lighting before night sorties when I was in the air force, and the wander lights in the cockpits had red filters for reading maps.

I imagine that if visual was particularly useful during things like docking they'd just make sure the tricky bits happened in plenty of light. It's not like you generally have long to wait to get the sun back.

[Vanamonde]

Don't most military aircraft have a low-intensity setting for night flying? I believe they used to, anyway. And turning down the brightness would be a lot easier than trying to make all the indicators and instruments shades of red.

[peadar1987]

Hmm... Maybe it's not that red light is good for night vision, perhaps it's just that you need to keep some of the sensors in your eye sensitive for the transition to low light. Whether those are blue & green from using red lighting, or green & red from using blue lighting, and so on mightn't matter.

Anyone know more about this than I do, and able to give a definitive answer?

[WestAir]

I have an old book on aviation psychology. This is what it says on night vision:

DARK ADAPTION

Rods are able to detect images in the dark because they create a chemical called rhodopsin' date=' also referred to as visual purple. As visual purple is formed, the rods can take up to 30 minutes to fully adapt to the dark. [...] The rods are least affected by the wave-length of red light so red cockpit lighting has been used in the past to help preserve night vision. However, since red lights refracts less than other colors of white light, objects are no longer in focus using only red light, and it is more difficult to transition from near to distant vision. In addition, red light masks any red colored instrument markings or map symbols. It is recommended that you use red light only when trying to enhance the adaption process. Low-level white light illuminating the instruments and within the cockpit should be used in flight.

[lajoswinkler]

Red light indeed is the least powerful radiation, but it's way more important to use dim light. Bright and rich red as "night vision protection" is actually a myth.

If you can choose between decent red illumination and dim white light, choose the latter.

In fact, retinas have the most sensitivity for green, so you can use very dim green and still protect your night vision while being able to do your work.

[Decent Weasel]

My understanding was that, yes, red light left rods unactivated, so they would stay sensitive and night-adapted, so red's ideal for general illumination. Rods, however, pick up green quite well, so general green illumination would blow out rods and kill night vision. However, green is also more legible, so green is ideal for instrument markings, where its brightness makes it pop out and it doesn't cover enough of the visual field to desensitize rods.

I had figured red would be of little use for docking, since if it came to docking nightside, you'd probably just have some lights on the outside of your ship you could flip on. Bingo, bright as day.

[vger]

I guess then it begs the question, is green more common now because of a defunct ideas about red, or just because visual confirmation isn't as important as it used to be?

In one case though, if you weren't just staring at screens, you wouldn't want to be on the bright side of a comet while trying to grapple it.

Psychologically, maybe red in space is a bad idea anyhow. Psychologically it's just more unnerving than green, which is not something you want when you have a handful of people trapped in a tin can long-term. But wasn't red often used in subs? Or is that just a Hollywood propagated myth?

[Decent Weasel]

Not sure about subs. I think the proliferation of greenish lighting in military aircraft is due to night vision devices becoming more commonplace. Just as human rods are insensitive to red light, night vision devices are insensitive to that particular wavelength of green light.

[Seret]

Bright and rich red as "night vision protection" is actually a myth.

I don't think anyone's ever suggested using bright red lighting have they? Whenever I've seen it used it's been pretty dim. Better than no lighting, but still pretty hard work for things like reading. It's normally used in staging areas where people are moving into a dark environment or on torches for reading maps, there's no need for it to be bright.

But wasn't red often used in subs? Or is that just a Hollywood propagated myth?

From what little I know about subs I gather it is routine to send people up the tower whenever they're running on the surface. So having those people dark-adapted before they went up the ladder would be useful. You'd switch to red lighting before surfacing at night to allow your boys time to adapt so they're effective as soon as they go up.

I think the proliferation of greenish lighting in military aircraft is due to night vision devices becoming more commonplace.

Correct. The instruments on military aircraft do have to be compatible with NVGs, meaning they don't emit anything towards the red end of the spectrum that would wash them out. You are starting to see a lot more use of NVGs these days, even on fixed wing and in civilian use.

Edited August 26, 2014 by Seret

[Idobox]

Remember the movie was shot in 68. Computers and automation were much less developed than today, so visual tracking and manual controls seemed much more important. I'm not even sure they had synthetic aperture radars at the time, which would be essential to track things with a good time resolution (remember the radar thingie with a green line spinning roughly once per second and going ping for each echo? you don't want to use that for docking).

But mostly, I think it's an esthetic and symbolic choice by Kubrick, the color chosen being quite organic.

[lajoswinkler]

I don't think anyone's ever suggested using bright red lighting have they? Whenever I've seen it used it's been pretty dim. Better than no lighting, but still pretty hard work for things like reading. It's normally used in staging areas where people are moving into a dark environment or on torches for reading maps, there's no need for it to be bright.

Well, the myth goes that you can use even very bright light, but exclusively red, and your night vision will be fine, which is not true.

If one needs to light a map, read something, etc, very dim white is the best because only red wavelength is not easy to focus on and monochromatic lightning doesn't allow for recognition of red stuff on white background, etc.

If one just needs to avoid obstacles or if a glowing display is needed, dim red is perfectly fine.

But mostly, I think it's an esthetic and symbolic choice by Kubrick, the color chosen being quite organic.

Ditto.

[Seret]

doesn't allow for recognition of red stuff on white background, etc.

Military maps are designed for use with red light for exactly this reason. Using a red filtered torch is pretty much Fieldcraft 101. Using a white light is not considered a healthy option, it's too easily spotted by folks who don't have your welfare in mind. If you have to use white you have to make damn sure no one else can see it.

[lajoswinkler]

Military maps are designed for use with red light for exactly this reason. Using a red filtered torch is pretty much Fieldcraft 101. Using a white light is not considered a healthy option, it's too easily spotted by folks who don't have your welfare in mind. If you have to use white you have to make damn sure no one else can see it.

I was talking about general usage, such as skygazing, etc. Monochromatic red light can be quite confusing.

[Decent Weasel]

You guys are awesome

[Sky_walker]

I was talking about general usage, such as skygazing, etc. Monochromatic red light can be quite confusing.

I don't know about you, I'm hardly an expert in that field, but from the only 2 stargazing maps I have: one is designed to work perfectly fine with red lighting, another one glows red itself (iPad app - night mode).

Well, the myth goes that you can use even very bright light, but exclusively red, and your night vision will be fine, which is not true.

If one needs to light a map, read something, etc, very dim white is the best because only red wavelength is not easy to focus on and monochromatic lightning doesn't allow for recognition of red stuff on white background, etc.

If one just needs to avoid obstacles or if a glowing display is needed, dim red is perfectly fine.

If you're stargazing - you want your eyes to be as sensitive as possible. Using red light allows it far better than the white light does.

Of course you are free to use whatever you want and whatever you feel comfortable with (red lighting can be disorienting if you're using it first time in your life) never the less - once you run it for several times and adjusted yourself - it's much better than white.

IMHO, future big spacecraft, if they will be ever built, do not need any WWII submarine - style red lights.

Cabin walls will not have any windows to look at the dim objects, they will be covered with big computer screens, with superimposed data from various sensors.

Inside lighting will be bright, to keep crew alert.

Yep. Proper lighting is very important to day-night cycle and that - is essential for performance, especially in long term missions.

So filling a spacecraft with red lighting would be very counter-productive. It needs to be as close as possible to a daytime sunlight on a surface of the earth.

Edited August 26, 2014 by Sky_walker

[YNM]

As far as I can tell from watching night sky (and watching a simulation in a planetarium), red lights are somewhat useful, even compared to dim white light. Sure, most red light lamp sold is slightly too bright than required, but the re-adaptation is slightly faster than even dim white light.

Not sure what's the reason for planes, but it could be just that if the lighting inside is too bright, you can't see anything outside (the glass reflects it back) - so red light is used. Same thing in cars etc.

[vger]

If you're stargazing - you want your eyes to be as sensitive as possible. Using red light allows it far better than the white light does.

Of course you are free to use whatever you want and whatever you feel comfortable with (red lighting can be disorienting if you're using it first time in your life) never the less - once you run it for several times and adjusted yourself - it's much better than white.

If you're out in a field, you're guaranteed more darkness with red light anyhow. Plants absorb almost all of the red so there's minimal reflection.

Yep. Proper lighting is very important to day-night cycle and that - is essential for performance, especially in long term missions.

So filling a spacecraft with red lighting would be very counter-productive. It needs to be as close as possible to a daytime sunlight on a surface of the earth.

Well that'd be interesting. "Mood lights" on a spaceship synched to a 24-hour day cycle.

Speaking of which, if any of you out there like me have had insomnia issues from working on a computer before bed, give this a try. Just be careful if you're doing artwork where color is essential. http://justgetflux.com

[Idobox]

Well that'd be interesting. "Mood lights" on a spaceship synched to a 24-hour day cycle.

http://justgetflux.com

I'm pretty sure they dim the lights on a 24h cycle on ISS for that exact reason. It must be confusing enough to witness dawn every 90 minutes.