Of brightness perception and 1 Lumen Dog Walking - Henry Schneiker is right…

[wweiss]

Of brightness perception and 1 Lumen Dog Walking - Henry Schneiker is right…

I bought a 200 Lumen HICRI HDS Rotary last month and initially wondered what use it would be. It was very well made, but its max output was 200 lumens. I own a DS4 and a TC20, either of which could melt this thing to a puddle of molten aluminum. I own Hound Dogs and Wildcats, M61HOTs and 91Bs. All of them far out-lumen this very expensive, but very well made gadget. I was regretting spending the big money for this light when I happened to read Henry Schneiker's FAQ website page section - How can I see further?…

It was a revelation.

Following Henry's advice, I now use his great light to walk the dark woods, trails and rural roads of southeast CT set to - 1.1 Lumens. Sometimes, if it's dark enough with no moon, I go down to - .15 Lumen. I can see just fine. And the single RCR123A Efest lasts for 22-45 hours or more before a recharge.

From the HDS website:

"We are going to show you a simple method to take advantage of how your eyes work and how your flashlight works to see the furthest possible distance - further than you can see with other flashlights with the same output rating. But first, you need some additional information so you understand how this method works." ---- Henry Schneiker

"…The answer is dark adaptation. With the bright light, it is difficult to avoid over illuminating the scene and ruining your dark adaptation. With dim light, it is easy to build your dark adaptation, which counts as several additional brightness levels when you turn on the maximum output. Two additional brightness settings allow you to see 50% further. Three brightness settings allow you to see 84% further. Four brightness settings allow you to see 125% further - that's over twice as far." ---- Henry Schneiker

Try this at home. Go out into the dark (woods road, warehouse, country lane, trail) at the lowest level your light has and let your eyes dark-adapt (about 7-10min). You should find that even the 'moonlight' settings on most lights are too bright. If something does bump in the night just outside your low level glow, do a tactical high blast to see it and you will be amazed at how you will think you've got 20,000 Lumens in your hand, not 200.

Since it's wise to carry at least two lights, I have the HDS Rotary for low-lumen guidance and the latest version of the Armytech Predator Pro (warm) - probably the best pocket thrower available - for a very high, long throw-blast. With this method, batteries last for many hours and run-time worries a thing of the past.

 

[lion504]

Good post! You mentioned that you have a Hound Dog but that the Predator Pro is a better thrower. Why do you prefer the Armytek? Can you compare the HD and the Predator Pro? Thanks.

 

[bykfixer]

Like pixel-wars, lumen wars has been fraut with misinformation now disguised as necessary.

A Maglite Solitaire for example was plenty bright for a ton of uses until they said it wasn't. A 2C or D bulb'd light was plenty bright for nearly 100 years. The little 2 cell SureFire 6 was seen as "holy crap that's bright" for a decade.

If your photo needs to be blown up to the size of a roadside billboard, then all those pixels are great. If you need to light up a city block or can run 45mph then sure all those lumens are great. Back in Lincoln's day they got around just fine by candle light. Not ideal for reading by but definitely kept them from crashing into the outhouse at 11pm.

 

[lightfooted]

Henry's a good salesman.

I'm not going to say that there is no truth to what he said...because obviously there is some. However there is (was?) posted here somewhere much information from lots of research into Darkness adaptation and it was fairly conclusively proven that it takes several days to fully adapt to darkness on the level that some people think (or claim to be able to do themselves) can be done in mere minutes. I remember a reasonable portion of that discussion and most of those making claims to having dark adapted vision, simply didn't. Ultimately the recommendation was to use as bright a light as was needed to see what you need to see, clearly. Ramping up until comfortable with the picture. Having blinding brightness serves other purposes than navigating a well known path in complete darkness and isn't necessarily a capability everyone needs.

Also there is this problem of city night-time illumination. Those of us not fortunate to live outside the confines of a larger city have to deal with the glare produced by street and parking lot lights that are sometimes capable of tens of thousands of lumens. It's one thing to peer out into the murky darkness of a rural property where the only illumination is starlight. It's very easy for those 200 lumens to travel across several hundred yards but when you've got 10,000 lumens reflecting off of a lightly colored building or worse...actual polished metal surfaces...those 200 lumens aren't going much further than your breath into that dark corner near where you parked your car. It will barely be noticeable.

I've put this to the test more or less. I used an old XP-E drop-in in my Solarforce and took it to work where this is pretty much the environment I described above. Sure, up close it was usable but anything more than say 30 feet and it became nearly impossible to see into the dark areas. My brighter (400+ lumens) lights overcame this easily. Low powered lights certainly have uses and I would never get rid of a flashlight just because it was "underpowered" but I also don't think one should eschew more light just because our ancestors got by with rushlights. They also got by without wheeled carts and metal tools and electricity.

 

[Burgess]

So VERY true !


Great post here.

lovecpf


I'm 66 years old, and for most of my life,
everyone's standard flashlight was 2 "D" cells with a PR-2 bulb.


This produced about 10 to 15 Lumens with new batteries,
and is *STILL* my standard yardstick of measuring light output.


35 years ago, I bought my first Mini-Maglite (2xAA),
and that produced similar lumens in a Much smaller form-factor.
EDC'd this handy & useful little gem for Decades !


In total darkness, with dark-adapted eyes,
it's amazing what a single lumen can do.

Truly an Eye-Opening experience !
( pun intended )


_

 

[thermal guy]

Yes if your eyes are used to the dark you don't need much light. My HDS set at .33 lumens is plenty to walk around the house with. In fact 10-15 lumens is way to bright. But I would never walk around my woods with a light set to 1 lumens. Why would you. Yes if there's no other light pollution you can see the trail but that's about all.Low lumen lights are great for preserving your night vision or to stretch runtime to the max in a emergency but got to have a high to them with some throw for me to be a truly great outdoors light.

 

[wweiss]

To me, the Predator Pro (latest version) sends a much brighter, more compact throw farther downrange in an easier to carry form-factor than the Hound Dog. It really burns through the night.

 

[wweiss]

I did specify that I was doing this in a dark area - not a very urban area like Northern NJ, where I used to live.
If it in fact, took several days (all spent in a deep mine?) to dark adapt, our cave dwelling and nomadic ancestors would not have lasted very long - and there wouldn't be any astronomy clubs.
See this research: https://webvision.med.utah.edu/book/part-viii-psychophysics-of-vision/light-and-dark-adaptation/

 

[wweiss]

I do get high - with the Predator Pro...

 

[kamagong]

However there is (was?) posted here somewhere much information from lots of research into Darkness adaptation and it was fairly conclusively proven that it takes several days to fully adapt to darkness on the level that some people think (or claim to be able to do themselves) can be done in mere minutes.

Given that the average human needs to sleep eight hours in a 24-hour day, is it even possible for one to fully adapt to darkness? Seems like the adaptation period would reset every time one woke up.

 

[thermal guy]

8 hours of sleep! LOL I have 3 kids. Haven't had more then 5-6 hours of sleep in like 15 years😂😂

 

[RetroTechie]

Brightness levels are perceived relative to surrounding objects. On a dark night, a few lumens can put 100x more light on the area you're aiming at, vs. what's next to it. Making that area quite visible. In full daylight, several hundred lumen do nothing.

Human eyes are capable of handling brightness levels that differ by orders of magnitude. Take a walk in a dense forest, on a sunny day. The darkest patches you see, can be like >10,000x darker than surfaces that catch direct sunlight. But these differences are experienced as a 'linear' scale.

Given that the average human needs to sleep eight hours in a 24-hour day, is it even possible for one to fully adapt to darkness? Seems like the adaptation period would reset every time one woke up.

Perhaps. But your eyes go most of the way there in much less time. Coming from a well-lit area, it takes my eyes in the order of 10..20 min to adjust. But the other way around, dark adaptation is not immediately 'destroyed' either. It's kind of a "fast attack, slow decay" thing (or should I say "fast decay, slow attack"? ).

As for the OP's trick: this works best with a thrower. Even a modest amount of spill can illuminate nearby objects (like the ground you're standing on, branches / leaves of nearby trees, fog, snow etc), and this can greatly reduce your eyes' dark adaptation. Little or no spill -> dark adaptation stays in place & the light on far away object does its thing.

 

[thermal guy]

Yes you don't need long to get your eyes adapter to the dark. If I go to sleep and wake up a few hours later"I'm getting old" I need very little light to head to the bathroom.

 

[wweiss]

On the subject of waking up to go to the necessary, ever notice that even though your eyes have been shut/sleeping for hours, they are not dark adapted to your room until you use them for a few minutes?

 

[Poppy]

When I was a kid the 2 lumen incandescent maglite solitare was enough for me.
It was sufficient to light up the edges of the path I was walking on in the woods.
It may or may not have produced enough light for me to discern slight differences in height, so as to mark holes that are filled with leaves.

When I was a kid, I was very resilient. Uneven surfaces were no problem. Even if blindfolded, surfaces that had less than 6 inches in differences in depth, were not a challenge. I could walk the path without looking down. I would shine the light ahead to see where I wanted to go. There was never a fear of stumbling, and falling.

Yes my friend, things, and times have changed. My night vision is not as sharp as it once was. My footing is not as sure footed as before, and if I fall I am more likely going to get hurt. Therefore one or two lumens is NOT enough for dog walking, or for that matter... Poppy walking.

Additionally, I AM in Northern NJ.

For the most part, dog walking occurs in the street. The light is so that car drivers see me, and don't run me over.
When my daughter walks the dog at night I give her a light with a diffuser set at about 200-300 lumens.

 

[kuzuna]

I think it's a testament to how good we have it these days where a light running off of one battery can "only" put out 200 lumens, and it's a testament to the influence of advertising that a 200 lumen high is considered inadequate for an EDC light.

 

[peter yetman]

I think it's now time for this....

Archimedes' Graph, one of my favourite things.
P

 

[archimedes]

.... Archimedes' Graph, one of my favourite things.
P

Mine too

 

[CigarPundit]

When I was a kid the 2 lumen incandescent maglite solitare was enough for me.
It was sufficient to light up the edges of the path I was walking on in the woods.
It may or may not have produced enough light for me to discern slight differences in height, so as to mark holes that are filled with leaves.

When I was a kid, I was very resilient. Uneven surfaces were no problem. Even if blindfolded, surfaces that had less than 6 inches in differences in depth, were not a challenge. I could walk the path without looking down. I would shine the light ahead to see where I wanted to go. There was never a fear of stumbling, and falling.

Yes my friend, things, and times have changed. My night vision is not as sharp as it once was. My footing is not as sure footed as before, and if I fall I am more likely going to get hurt. Therefore one or two lumens is NOT enough for dog walking, or for that matter... Poppy walking.

Additionally, I AM in Northern NJ.

For the most part, dog walking occurs in the street. The light is so that car drivers see me, and don't run me over.
When my daughter walks the dog at night I give her a light with a diffuser set at about 200-300 lumens.

I just found my Maglite Solitare in a drawer I was cleaning out. Man, that thing is so skimpy. I'll hang onto it for nostalgia's sake, but I would never use it. Waste of a battery IMO. My Rovyvon A5 is much smaller, glows, has side lights for reading, a UV light, puts out 550 lumens, and recharges in minutes via USB. Hell, the thing smokes my old D cell maglight. The simple fact is that flashlights, as with all technology, are far better now. For my money, I want as much light as I can get for a given size. Virtually all UIs allow you to set lower outputs if that is what you want/need in a given situation. Having more light on hand is 100% a good thing.

 

[idleprocess]

Ah, extremes. It's a testament to both making due with what was available that the likes of the Mag Solitaire was a sufficient EDC light back in the day; a testament to the advancement of technology that 1000 lumen EDC lights are accessible. Personally I'm glad that we now have both - with the upside that the lowest output modes on LED flashlights can mean days or weeks of runtime.

At times, sub-lumen lights have their uses - generally in levels of darkness where night vision alone isn't sufficient yet there's still value in not trashing it.

Also, at times, the >10 kilo lumen lights on the market have uses, although I confess I've yet to routinely encounter such use cases personally (thus despite my interest in all things Emisar I've yet to procure the D18).

Between those extremes one finds the majority of the use cases - especially in the urban and suburban environments that most of us live in where ambient night lighting never approaching levels of darkness that mere moonlight or starlight provides.

I can say that I've wanted for lack of 10 kilo lumen output more often than sub-lumen output, but it's never an urgent want.

I will say that in the lumen wars one thing that seems to be missing is an appreciation for using one's night vision when appropriate. When I was younger I often realized that night vision was sufficient for most navigation while the flashlight was best reserved for tasks. There were exceptions of course - sometimes it was too dark or treacherous to navigate and some tasks one can do without looking at the work to be done. But under most conditions in the wilderness or countryside away from artificial light sources there's enough moonlight or starlight to walk around and maintain greater spacial awareness than if you're blazing away with a flashlight, shutting down those rods and largely limiting your perception to what the beam is illuminating.