Can someone explain to me the use of a light that makes <10 lumens?

[deusexaethera]

So you're saying that a flashlight is all the keeps you from getting mauled to death by predators when you get up to take a leak at night? I guess you do NEED one, then. Progress, indeed!

I'll kindly bow out of this discussion to let the thread wander back on course.

-John

You know what I mean.

"If you ask where the bathroom is and someone hands you a flashlight and says 'May the Force be with you', you might be a redneck."

(I'm not a redneck :devil🙂

 

[deusexaethera]

In response:

1) when you've been married for a double-digit number of years, eating home cooking every night, your old lady will stop putting up with any of your bull$*#%, and you'll start being a little more careful about not waking her up. While you may be able to see your way to the can, in previous posts, you mention just turning on the lights. You wife will quickly put a stop to that.

I wasn't really going to turn on the lights to see my way to the bathroom.

2) after about age 40, you'll start getting up to go to the bathroom a lot more often than you do now. Your vision will get worse, too, so a little more light will help.

I guess I'll have to wait and see on that one. (pun intended)

3) I don't "let" my kids keep their toys in my bedroom, but they're kids, so you'll find stuff strewn in the most random places. And I'll tell you what, stepping on a small lego piece buried in the carpet in bare feet will make you say naughty words.

When I was younger, I used to enter the living room by running and jumping over the big puffy chair in my way, then sliding on the carpet and stopping in front of the TV. One time there was a pile of wooden blocks in my designated landing spot, and I caught them right on the soles of my stocking feet. My brother caught a few things too, but not on his feet. Never happened again.

That being said, I do see the validity of your points.

 

[deusexaethera]

Yes, the little legos are painful. My personal favorite was stepping on one of my daughters earrings that was laying on the carpet. The post went right through my skin and stuck in my foot. 😱

Ah god, that one's making me squirm! One of my coworkers' girlfriends is a seamstress (or tailoress, if you prefer), and he said one time she dropped a sewing needle on the carpet. He later found it, with his foot.

My personal best was when my brother was spinning a wooden top on the kitchen counter, and my mother needed the counter space, so I grabbed the top while it was spinning, not realizing that he had been chewing on it and the edges were covered with splinters. The top drove a 3/4"x1/8" splinter about halfway into my fingertip. It took that sucker ten solid minutes to start aching.

 

[deusexaethera]

Cops and spys are but two exaamples. Have you ever been to a live stage play or even seen a live act in a niteclub? Those there would smile to find that you had no idea of their presence, as you have indicated. That was their intention. It worked. It's part of what you pay for when you buy a ticket. It's not really magic up there on the stage -- it's something that's been practiced and sold to you, whether you understand what your eyes are telling you you're seeing or not.

Nope, never been to a magic show. Just knowing it's fake makes me lose interest.

In a much more general vein: If many people weren't working behind the scenes with dim lights those reading this wouldn't have most of the products and services that they now take for granted. No products shipped across the oceans. Yikes -- no Nikes! No fish caught by commercial fishermen. No flights after dark -- passenger or freight. I'll leave the million things that the military does with dim light for others to ponder.

The Western world, as we know it, would nearly come to a complete standstill if there were no lights dimmer than 10 lumens.

Alright, alright, I get the point.

I prefer Adidas.

 

[Cheapskate]

i'm curious. would a 10 lumen red light save more night vision than a .5lumen white led.

is it the color or output..

The human eye contains four types of light receptor cells. There are three types of cone cell which are sensitive to red, green and blue wavelengths respectively.

The fourth type of cell are the rods. The are exquisitely sensitive to light - a single/quanta/photon - but are not sensitive to long wavelength light - red. When your eyes are dark adapted, you see using the rod cells.

When using a red light at night, you are seeing using only the red cone cells, not the rods. Using the brighter red light will have no impact on your dark adapted rods, but the dimmer white one will, because the light contains higher wavelengths that the rods are sensitive to.

 

[Brad]

The human eye contains four types of light receptor cells. There are three types of cone cell which are sensitive to red, green and blue wavelengths respectively.

The fourth type of cell are the rods. The are exquisitely sensitive to light - a single/quanta/photon - but are not sensitive to long wavelength light - red. When your eyes are dark adapted, you see using the rod cells.

When using a red light at night, you are seeing using only the red cone cells, not the rods. Using the brighter red light will have no impact on your dark adapted rods, but the dimmer white one will, because the light contains higher wavelengths that the rods are sensitive to.

That is the best explanation I've seen yet. Makes sense. Thank you for the info. :thumbsup:

Brad

 

[EngrPaul]

I can quickly think of a few situations where too many lumens is bad.

• Help reading a menu in a dark restaurant.
• At the movie theater
• Checking on the kids
• Illuminating a remote control while watching a movie
• Going to pee without turning the lights on

I have a floody Fenix E1 with SSC P4 for these purposed. And now a modified streamlight nano

 

[Sub_Umbra]

Nope, never been to a magic show. Just knowing it's fake makes me lose interest...

Emphasis mine.

I wasn't writing about magic shows. I was referring to the magic created on stage by any performer who causes one to suspend disbelief while paying money for the privlege. I'll try to be less subtle.

News flash: All entertainment is fake! It is all very carefully packaged. It is plastic. What the audiense sees and hears is determined ahead of time. It is not random. It's not what it seems. Particularly what goes on in the background. Even the news or anything else you pay to watch (with your money or by enduring ads.) In the sense that many people like yourself are unable to grasp that, it is all magic of a very high order. Your views would appear to be a testimonial to entertainment techies everywhere. As I pointed out earlier,

... they love that aspect of the relationship...

The less the audience understands about the process the more fun it is for the techies.

 

[LEDAdd1ct]

"When using a red light at night, you are seeing using only the red cone cells, not the rods. Using the brighter red light will have no impact on your dark adapted rods, but the dimmer white one will, because the light contains higher wavelengths that the rods are sensitive to."


Respectfully, I must disagree. I woke up somewhere between two and four A.M. this morning to visit the bathroom. We are having our main bathroom redone, so I had to venture downstairs to an auxillary toilet. I grabbed my miniM@g retrofitted with a red Niteize dropin, running off a single AA cell plus a dummy cell. I had to cover the light head with my fingers to drop down the output. I know there is a thread hanging out somewhere (I'll look in a minute and find the relevant post) where a member wrote something along the lines of, "Between a *very* dim white light and a *very* dim red light, the red light will affect (negatively) one's night vision to a lesser extent. However, a red light of sufficient brightness *will* cause one to lose one's night vision." I am aware of the argument based on wavelengths, and I really wanted to believe it. However, I can state from direct empirical observation that even those three measly 5mm red LEDs off a single AA alkaline cell (too weak to use in any other light) are too bright for fully dark-adapted vision.

So, yes, there is an excellent use for a light source that puts out far less than ten lumens.

 

[greenlight]

The Western world, as we know it, would nearly come to a complete standstill if there were no lights dimmer than 10 lumens.

I thought the same thing would happen when they discontinued the Inova X1.v1, but it hasn't stopped, yet.

 

[Sub_Umbra]

I thought the same thing would happen when they discontinued the Inova X1.v1, but it hasn't stopped, yet.

The Inova X1.v1 -- R.I.P. :sigh: I only have a couple new ones left. Mrs Umbra has been running all manner of tech shows with the early X1s for years and years. She gets about 2-3 years out of each one. She's going to go into shock when the last one dies. I wish I had ten more of them...

 

[asdalton]

LEDAdd1ct -

Yes, in order for a light to preserve your night vision, it must be both red *and* very dim. Most red LED lights and red-filtered incandescent lights are too bright for this purpose.

 

[electric sheep]

Most filters let through more than the red light that would be usefull and allow disruptive wavelengths.

 

[henry1960]

I use my E01 Fenix for during the night episodes which work really well for me but do admit sometimes i wish i had a light with a lower lumen. 😀

 

[Black Rose]

Also, I'd like to add that humans existed for about 200,000 years prior to the invention of the flashlight. They all did just fine.

True, but perhaps Ogg lit up a torch while getting up from his cave in the middle of the night to address natures call behind a tree/rock/dinosaur 😀

 

[deusexaethera]

I can quickly think of a few situations where too many lumens is bad.

• Help reading a menu in a dark restaurant.
• At the movie theater
• Checking on the kids
• Illuminating a remote control while watching a movie
• Going to pee without turning the lights on

I have a floody Fenix E1 with SSC P4 for these purposed. And now a modified streamlight nano

I'm amused that this one keeps coming up. Is it really that bloody hard to sit down? I dunno about you, but when I get out of bed to take a leak at night, I dislike being upright (which is why I wasn't upright before), and sitting down lets me remain as groggy as possible so I can fall asleep faster.

 

[deusexaethera]

Emphasis mine.

I wasn't writing about magic shows. I was referring to the magic created on stage by any performer who causes one to suspend disbelief while paying money for the privlege. I'll try to be less subtle.

News flash: All entertainment is fake! It is all very carefully packaged. It is plastic. What the audiense sees and hears is determined ahead of time. It is not random. It's not what it seems. Particularly what goes on in the background. Even the news or anything else you pay to watch (with your money or by enduring ads.) In the sense that many people like yourself are unable to grasp that, it is all magic of a very high order. Your views would appear to be a testimonial to entertainment techies everywhere. As I pointed out earlier, The less the audience understands about the process the more fun it is for the techies.

That would be why I watch about two hours of TV a week, and play maybe an hour of videogames a week, and see maybe one movie every couple of years. I really have absolutely no interest whatsoever in staged performances -- including reality shows.

 

[Marduke]

I'm amused that this one keeps coming up. Is it really that bloody hard to sit down? I dunno about you, but when I get out of bed to take a leak at night, I dislike being upright (which is why I wasn't upright before), and sitting down lets me remain as groggy as possible so I can fall asleep faster.

And what about going to and from the bathroom? Unless your toilet is right next to your bed (in which case you have other issues), you generally have to walk to the bathroom, which means navigating through some portion of the house, around any number of potential obstacles.

Most of the comments about going to the bathroom with a light is more about the journey, not just the destination.

 

[Zatoichi]

Most of the comments about going to the bathroom with a light is more about the journey, not just the destination.

That's true for me. Once I know I'm positioned correctly, I'm pretty much as good an aim in the dark as in the light. Not that that's saying much... :naughty:

 

[Benson]

"When using a red light at night, you are seeing using only the red cone cells, not the rods. Using the brighter red light will have no impact on your dark adapted rods, but the dimmer white one will, because the light contains higher wavelengths that the rods are sensitive to."

OK, I'm no expert, but what I know of this, I'd say there are two curves here: the falloff of the rods' response to red light (probably very low, but not quite zero, at typical red wavelengths; and the spectrum of a "red" light source, which may (especially in the case of filtered red light, and less so with red LEDs) be low but non-zero in regions where the rods have a significant response -- with bright enough red light, the overlap of these curves will reach significant levels, and kill night vision, but still less than equivalent white light.

The Western world, as we know it, would nearly come to a complete standstill if there were no lights dimmer than 10 lumens.

I think that's a little strong -- a boom in the diffuser & attenuator industry isn't really TEOTWWAWKI.