How Many Lumens???

[NE450No2]

How many Lumens are necessary?

A "flashlight" is a Tool, carried to do a "job".

So how many lumens are required to;

Read a map.

Get up in the night to go to the bathroom, "do stuff" in a tent, or a bedroom.

Walk around in the dark on a known trail.

Walk around in the dark, on an unknown, or on no trail in the woods.

Blind an attacker.

Search the woods for animals, wounded or not.

Search the Woods for "whatever".

While I have my own ideas...

I am curious to hear your thoughts.

 

[Marduke]

It depends on too many other things. This thread will give you some insight.
http://www.candlepowerforums.com/vb/showthread.php?t=239548

 

[Caesis]

I can blind someone with my 215 Lumen Romisen.

Can also see as far as I need to in a town, and it's good in the woods, too.
But if I want to walk through a house at night to the bathroom with it, I'll probably blind myself while shining it at a wall ... way overkill.

I know a M@G solitare is 5 lumens at full battery, and that's enough to "Do stuff" in a tent.

For general "whatever" use, I think 100 lumens is a good number.

 

[Databyter]

Read a map. 50-100 lumens ( some maps have really small print)

Get up in the night to go to the bathroom, "do stuff" in a tent, or a bedroom. 25 - 50 lumens

Walk around in the dark on a known trail. 50+ lumens

Walk around in the dark, on an unknown, or on no trail in the woods. 130+ lumens

Blind an attacker. 150+ lumens depending on factors (ambient light, spot or flood, duration of blindness). For really effective longer lasting defensive blindness 400-600+

Search the woods for animals, wounded or not. 225 minimum preferably 600 +

Search the Woods for "whatever". 400 - 600+ More lumens = faster searching and less walking.



EDIT:
These numbers are my opinion for ideal, as another poster said, 5-10 lumens will work in a pinch for common tasks where your just need visual "clues" etc..

Also:..

For blinding attackers, I don't know if anyone has ever made a thread about this but there are several factors in my personal experience. There are two basic factors at work.

Factor number 1 is pupil dilation which eliminates night vision especially in dark ambient light conditions. THis only lasts a few seconds to half a minute or so depending on ambient light conditions. A really bright light will dilate your eyes so much that it will take a while for the defensive reaction to relax.

Factor number 2 is creation of a lasting afterimage which inhibits vision for some period of time regardless of night vision or pupil dilation.

The afterimage will be worse and longer lasting the larger the pupils were open when exposed to bright light, so if you blind someone in the dark they will be more effected by afterimage than if you flashed them in the daytime. and of course it will be worse and longer lasting the brighter the light is. The afterimage of a very bright light especialy well aimed spot will pretty much completely blind a person for minutes.

Disclaimer: CPF Forums discourages purposeful aiming of lights into other peoples eyes. Informational purposes only.

 

[vtunderground]

My old Underwater Kinetics 4AA eLED can - and has - done all of those things very well (except for blind an attacker of course). And that light only has, what, 20 lumens? All I know is that when I've been out in the woods at night, I've never felt underpowered with that light.

With a lower output light, your night-adapted vision helps you to see things beyond the beam of the flashlight. When you bring out the powerful lights, you lose the night-adapted vision, so in a way you're just wasting lumens because your eyes are compensating for your flashlight being too bright.

My $0.02

 

[Databyter]

My old Underwater Kinetics 4AA eLED can - and has - done all of those things very well (except for blind an attacker of course). And that light only has, what, 20 lumens? All I know is that when I've been out in the woods at night, I've never felt underpowered with that light.

With a lower output light, your night-adapted vision helps you to see things beyond the beam of the flashlight. When you bring out the powerful lights, you lose the night-adapted vision, so in a way you're just wasting lumens because your eyes are compensating for your flashlight being too bright.

A very valid point for closeup.

Of course for searching and longer distances you need the lumens to see detail.

I think headlight beams on cars are getting out of hand for the very point you bring up.

It's getting ridiculously bright on the road to where if you drive all night like I do many fidiots will blind you in a typical night.

 

[mossyoak]

How many Lumens are necessary?

A "flashlight" is a Tool, carried to do a "job".

So how many lumens are required to;

Read a map. 1 lumen is sufficient

Get up in the night to go to the bathroom, "do stuff" in a tent, or a bedroom. .2 lumens

Walk around in the dark on a known trail. 5 lumens

Walk around in the dark, on an unknown, or on no trail in the woods. 40 lumens

Blind an attacker. 65 lumens

Search the woods for animals, wounded or not. 40 lumens

Search the Woods for "whatever". 40 lumens

While I have my own ideas...

I am curious to hear your thoughts.

i just typed it beside your questions.

 

[rmteo]

What matters is not Lumens but Lux - or Footcandles (density of the luminous flux incident on a surface).

You may be able to read a map with 1 lumen, provided the light source is close to the map. Move that 1 lumen source to 20 feet away and it is a whole different situation.

 

[Woods Walker]

Read a map. 50-100 lumens ( some maps have really small print)

Get up in the night to go to the bathroom, "do stuff" in a tent, or a bedroom. 25 - 50 lumens

Walk around in the dark on a known trail. 50+ lumens

Walk around in the dark, on an unknown, or on no trail in the woods. 130+ lumens

Blind an attacker. 150+ lumens depending on factors (ambient light, spot or flood, duration of blindness). For really effective longer lasting defensive blindness 400-600+

Search the woods for animals, wounded or not. 225 minimum preferably 600 +

Search the Woods for "whatever". 400 - 600+ More lumens = faster searching and less walking.



EDIT:
These numbers are my opinion for ideal, as another poster said, 5-10 lumens will work in a pinch for common tasks where your just need visual "clues" etc..

Also:..

For blinding attackers, I don't know if anyone has ever made a thread about this but there are several factors in my personal experience. There are two basic factors at work.

Factor number 1 is pupil dilation which eliminates night vision especially in dark ambient light conditions. THis only lasts a few seconds to half a minute or so depending on ambient light conditions. A really bright light will dilate your eyes so much that it will take a while for the defensive reaction to relax.

Factor number 2 is creation of a lasting afterimage which inhibits vision for some period of time regardless of night vision or pupil dilation.

The afterimage will be worse and longer lasting the larger the pupils were open when exposed to bright light, so if you blind someone in the dark they will be more effected by afterimage than if you flashed them in the daytime. and of course it will be worse and longer lasting the brighter the light is. The afterimage of a very bright light especialy well aimed spot will pretty much completely blind a person for minutes.

Disclaimer: CPF Forums discourages purposeful aiming of lights into other peoples eyes. Informational purposes only.

All of those levels seem to high. Heck I mostly use 2-15 in camp. 25-50 on most trails and for water/wood runs. Maybe 80-150 for looking a long way but only for a short time on unknown trails or places without any trail. As for map reading I am not walking around at dark with a map and compass looking for I don't know what. Seems like a big risk and for a map and compass you need somekinda orentation and the dark dank woods are all about dis orentation but heck this is just my personal experiance and everyone does their own thing.:)

Edit.

I also should reduce the 25-50 for known trails. Often I get away with less which was the case a few hours ago.

 

[Petersen]

Preety much what Mossyoak stated.....

I normally use the 0.08 setting on NT120 to check on the kids in the night ect.

But it's also a matter of how well each induvidual sees in darkness....personally I can see in "total" darkness outside with only the light from a few stars....

 

[Freeze_XJ]

Let's see...

Read a map. 5-25 lumen. If i only need to see how many intersections to go, a few lumen will do. For reading that damned small print or weird names, more is useful. Spoils night vision though.

Get up in the night to go to the bathroom, "do stuff" in a tent, or a bedroom. 0.5 - 10 lumen. An E01 can deal with that or might be too bright.

Walk around in the dark on a known trail. 2+ lumen. Usually the stars and moon (which is pretty bright once your eyes are dark adapted) will handle that. If you want, take a lowlevel light for it.

Walk around in the dark, on an unknown, or on no trail in the woods. 20+ lumen. Just to see nasty critters scurry away.

Blind an attacker. An LD01 on medium (40-ish lumen) is enough to see white lights everywhere for a few seconds if it hits you at night. If you want to be certain, and don't mind blinding yourself a bit as well, 200+ lumen should do. For longer distances add as much as you can.

Search the woods for animals, wounded or not. 50 minimum preferably 100 or more. The more light, the less you have to walk. A thrower is a better idea, to concentrate the lumens a bit better.

Search the Woods for "whatever". As above. Why send a man where you can send a beam?

 

[rookiedaddy]

I'm gonna be more specific with flashlight used:
Read a map. H501-Low
Get up in the night to go to the bathroom, "do stuff" in a tent, or a bedroom. H501-Low
Walk around in the dark on a known trail. H501-Med
Walk around in the dark, on an unknown, or on no trail in the woods. H501-High
Temporary Blind an attacker. H501-Strobe
Search the woods for animals, wounded or not. H501-High
Search the Woods for "whatever". H501-Med
:devil:

btw, it doesn't hurt to bring a TK40 along... :laughing:

 

[old4570]

Any Multimode Cree XR-E R2 flashlight powered by 2 x CR123A or 1 x 18650 .

Spend from 15USD to over 100USD , it will do the job .

If you buy a LEGO light , then it will leave you open to future Mods and spending , and plenty of options [ P60 Hosts ] , and customizing .

My fav Lego light is the Solarforce L2 , so many options .

1x18650 / 2x18650
2xCR123A / 3xCR123A
1xCR123A / 1xAA / 2xAA / 3xAA /

Just chose the drop in you want , body configuration [ Even No Body = L2micro ] and the battery of choice that fits in the body , and have a pimped out rig .
:poke:

Just depends on what you want ?

 

[gallonoffuel]

Similar thread from 3 weeks ago:

http://www.candlepowerforums.com/vb/showthread.php?t=239548

 

[Databyter]

All of those levels seem to high. Heck I mostly use 2-15 in camp. 25-50 on most trails and for water/wood runs. Maybe 80-150 for looking a long way but only for a short time on unknown trails or places without any trail. As for map reading I am not walking around at dark with a map and compass looking for I don't know what. Seems like a big risk and for a map and compass you need somekinda orentation and the dark dank woods are all about dis orentation but heck this is just my personal experiance and everyone does their own thing.:)

I'm sure your right, however if you notice I did put this in my post;

These numbers are my opinion for ideal, as another poster said, 5-10 lumens will work in a pinch for common tasks where your just need visual "clues" etc..

I wasn't really thinking camping trip, I was thinking "work" because I do all those tasks at work every night, with the exception of the tent..
If I was camping I would probably want to be much more low key and appreciate the beauty of the night. At work though it is my job to notice alot more so this colors my answer. I find that I need a fairly bright light to light up a few square feet of a detail map with small print for addresses for instance . While 2 - 20 lumens would work it would only light up a few inches and would have to be held closely. Thats fine for camping but not for responding to a strange addresses.

So in short I agree, with the exception of searching in the woods where I would still go as high as possible I'd cut my numbers to 30% for a lazy camping trip.

 

[Marduke]

2-20 lumens is only good for a few inches? How bad is your eyesight?

5-15 lumens has been the norm for a household flashlight for the better part of a century. It let's you see a hell of a lot more than a couple inches. For most of the above tasks, it is downright blinding.

 

[xcel730]

I haven't have much need for anything more than 100 lumens, even when venturing outdoors. I guess my life is not very exciting. However, that doesn't stop me from getting flashlights that exceeds 500 lumens :grin2:

At night, when my soon-to-be wifey is asleep and I have to navigate to the bedroom, the only light I use is my Ti La Petite Killer, which I have as a necklace. I think it only spits out about 5 lumens or so ... and even that's a little too bright. I have to cover it up with my hands.

 

[RobertM]

How many Lumens are necessary?

A "flashlight" is a Tool, carried to do a "job".

So how many lumens are required to;

Read a map. 1-3

Get up in the night to go to the bathroom, "do stuff" in a tent, or a bedroom. 0.5-3

Walk around in the dark on a known trail. 0-3

Walk around in the dark, on an unknown, or on no trail in the woods. 5-25

Blind an attacker. 100+

Search the woods for animals, wounded or not. 30+

Search the Woods for "whatever". 30+

While I have my own ideas...

I am curious to hear your thoughts.

See above in bold. Keep in mind that there are way too many variables to consider. For example, less incandescent light is needed when outdoors than with LED due to better color rendition (IMO). In addition, ambient light pollution is going to effect most of the above situations drastically as well.

 

[StarHalo]

So how many lumens are required to;

Read a map - ~2 lumens

Get up in the night to go to the bathroom, "do stuff" in a tent, or a bedroom - ~1 lumen

Walk around in the dark on a known trail. ~60 lumens

Walk around in the dark, on an unknown, or on no trail in the woods. Full moon, ~60 lumens. No moon, >200 lumens.

Blind an attacker. >200 lumens

Search the woods for animals, wounded or not. >200 lumens

Search the Woods for "whatever". >200 lumens

 

[Crenshaw]

I tried using my Quark on moon mode in the cinema, didnt work too well, its dark, and yet you're semi blinded by the screen, so you cant see well. needs at least the second mode

Crenshaw