Lumen task reference sheet

[DavidMB]

Is there any reference sheet out there that describes the useful applications for different lumen outputs? I'm thinking this could be useful guide that could evolve and improve over time. This reference list could vary greatly based on the type of beam, throw vs flood, but for this I'm leaning towards a general use lights that are more floody then throw. My other thought is to keep the description short and relating to the most widely used and known applications in order to give it the widest appeal. My rough outline below, any help is appreciated.

1 -Night adjusted eyes, navigating around a dark house
2.5 -Reading a menu in a dark restaurant
20 -Working on the inside of a computer
40 -Casting light on a work area, car engine, closet..
70 -Looking around in dark or dimly lit garage, nite time walk; cast roughly 15' to 25'
100 -
400 -
600 -

 

[StarHalo]

33 posts in 7 years? Speak up, man..

Any general use chart is going to vary a lot by the eyesight of the user; all the guys with great eyesight use less than a lumen for house navigation, and rarely have a use for anything over ~25 lumens.

 

[reppans]

I agree that such a chart will vary quite a bit based each individual's vision, and perhaps more importantly, based on their preferences. I'll admit to being way off on the low lumen side of the scale, but I consciously like to use my night vision to its fullest potential and I despise changing, charging and carrying spare batteries (all my lights are 1xAA/AAA).

If there is no, or minimal, ambient light I'll use 0.2lm moonlight (low) for your 1-20lm listings, and then kick up to 4lm (med) for your 40-70lm listings (like walking the dog). I use my 19lm mode (high) for general perimeter scans outside. My 80+ lm (max) modes are reserved for showing off, riding bicycles downhill at speed at night, and finding deer lurking in the woods (there're frack'n herds around my house).

On the other hand, if I've just walked inside from broad daylight, your lm numbers seem reasonable to me.

 

[DavidMB]

Star... Funny, yes very few posts and lots of reading over the last few years. I was not paying attention for a while too and now that I'm back I'm really impressed with how the technology has progressed.

4Sevens lights go down to .04 or .05 lumens. That's really low. I wonder if that would look much dimmer then my 1 lumen Sunwayman

 

[StarHalo]

I know the V-series Sunwaymans dim enough that you can look into the emitter comfortably.

In actual use, whole-single-digit lumens is actually a lot; in a power outage situation, 2 lumens ceiling-bounced is plenty to accomplish anything other than reading if you're by yourself.

 

[yifu]

Different people have different ideas of what lumen outputs are useable. Some prefer 20 lumens for close up work while some prefer 2, it's very subjective. For me, i use 1600 lumens out of a EDCed C2 for pretty much everything. It feels just like turning on a light. Why bother straining your eyes when you dont have to?

 

[cave dave]

I agree that a task based approach is useful, especially while setting up a programmable light like an HDS. However I think everybody is a bit different in what they like for the same task. I can easily get away with half or less brightness for the tasks the OP listed. For instance I find little use for lumen values between 0.5lm and 3lm. I find this level too bright for night preservation and too dim for simple tasks like walking from my car to my house, looking under a desk, inside a computer etc.

Its kind of frustrating to me that almost all multi-mode flashlights "waste" one of there 3 or so levels on something I don't find useful, and usually put it at the very start of the sequence so its just something I have to cycle through each time I turn the light on.

 

[TEEJ]

Sigh

You can't see lumens, its about lux...and beams are not the same size...so a floody 1 lumen is not as much lux to SEE WITH as a thrown 1 lumen would provide, and so forth.

So one 1 lumen light might have enough light to navigate by, and another might not.

One might make a dim globe of light, and one might make a 6" diameter hot spot.

You might be able to read by one beam shape, but not as well by the other, and so forth.

If your 70 lumen thrower is used to go for a hike on a rocky path, you can't see enough at a time to avoid tripping/stepping into holes, on snakes, etc...but you might be able to spot a bear 100' away.

If your 70 lumen flooder is used for the same hike, you might be able to avoid tripping/snakes, etc...but to the bear, there would be a small ball of light with lunch in the middle.

:D


There are PLENTY of sheets that list minimum, and sometimes maximum LUX values for tasks...how much for reading, working under a truck, an escape route, workingon a computer, reading, etc.

If you want to calculate the Lux a light would provide at the range, etc, you'd be using it...and then see if the resultant lumens to get that lux works, that's probably the most applicable.

 

[arnold ziffle]

10 lumens to walk in backyard at night. 30 lumens not to step in poo.

 

[angelofwar]

Also, 10 floody lumens and ten "laser beam" (TIR) lumens are two completely different worlds...

 

[TEEJ]

Also, 10 floody lumens and ten "laser beam" (TIR) lumens are two completely different worlds...

True Dat

That's why I try to point out that "Lumens" relative to task lighting, is misleading.

Its like talking about horsepower for a vehicle, w/o knowing if its in a go-cart, or a tractor trailer.

:D

 

[eh4]

Ok so lux is useful and lumens not so much, how about referene from 1 candle, with properly trimmed wick?Mmmmm, I feel that I am reinventing something here. Anyways, an unreflectored, shrouded candle will have the same lux at a given distance but less lumens than an unshrouded candle, but without the counter productive glare.