New Lights Long On Brightness, Short On Runtimes

Just wanted some views of the EagleTac G25C2 1030 versus the Klarus X11. Both lights appear to be very well made, but the runtimes of the EagleTac are disappointing, especially in the low modes. In fact, I've been very disappointed in the low mode runtimes of the Olight M20s. The earlier 320 lumens model had a low 5-lumen mode that was rated for 600+ hours (which is good enough to read by in a dark room or tent). But recent top performance lights seem to be concentrating on raw output only instead of practicality.

That said, I've heard some great things about EagleTac. They do seem a bit pricey. What are your views and experiences?

I can't complain about Klarus XT11's run time...with the 3400 mah 18650, I get over two and a half hours on high (~550-650 L)....and the lowest setting ~ 10 lumens, will go for about 2 weeks.

EagleTac is the wrong place to look if you're interested in low modes. Take a look at some Zebralights..

Just because a light says it can achieve a certain amount of maximum output, that still doesn't mean that you should run it on that all the time unless you require it. Seriously, would you want to redline your car every time you drive it around?

Save the max output for emergencies and stick to lower outputs. It will run for long and cool that way.

If you frequently come across situations where you are constantly using the maximum output of your flashlight, then it'd be wise for you to invest in a larger light, and have that run at lower output instead.

My solution is to buy lights which have "lego-able" bodies available, so that if I need more run time, I just screw-on a longer body for bigger batteries.
All my lights are like that, except my little cheap beater one-cell light.

It sounds like you are comparing manufacturer spec sheets. Since I've started testing my lights with a DSLR lumen meter, and also running side-by-side runtime tests, I'm starting to find that flashlight efficiency (within a given price/quality range) is a lot closer than the listed manufacturer specs might lead you to believe. You tend to find some manufacturers are conservative while others are - lets just say "liberal"- with their listed specs. You can also mine some of this info out of Selfbuilt's test, although he's focus on high lumen end.

For example, my Zebralight SC52 and Quark AA-XML both have a 0.3 moonlight and 2.7 low, but ZL's runtimes are listed as 2-3x longer. It turns out the ZLs runtimes make sense since its modes actually measure in the 1/2 to 1/3 range of the Quark. Many have said the XML emitter is not as efficient as the XPG emitter at lower lumen levels. However, in my runtime tests between those emitters in Quarks, the lumen difference basically accounted for most, if not all, the runtime difference.

The other thing is that battery consumption is quite linear with lumen output, while light perception is closer to a square/square root function. So small, essentially imperceptible, differences in lumens can result in significant differences in runtimes.

enomosiki said:

Just because a light says it can achieve a certain amount of maximum output, that still doesn't mean that you should run it on that all the time unless you require it. Seriously, would you want to redline your car every time you drive it around?

Save the max output for emergencies and stick to lower outputs. It will run for long and cool that way.

If you frequently come across situations where you are constantly using the maximum output of your flashlight, then it'd be wise for you to invest in a larger light, and have that run at lower output instead.

Click to expand...

There is some merit in this - but, in practical use...the lights are mostly protected (el cheapo direct drive's w/o protection, etc...are another story) and it doesn't hurt them to run at whatever max output they will let you run them at....

...which is OK most of the time, as the size/weight/form factor of a larger light is a disadvantage most of the time outside of momentum based defensive strategies.

It is therefore typically more advantageous to have a light that DOES work for you on its high output...as, otherwise, you could have used an even SMALLER light, and so forth.

enomosiki said:

Just because a light says it can achieve a certain amount of maximum output, that still doesn't mean that you should run it on that all the time unless you require it. Seriously, would you want to redline your car every time you drive it around?

Click to expand...

That was my first thought as well. But if you read the original post again, you'll see that he is complaining about the runtimes in low. That is, even the lows are inefficient. It's a reasonable complaint, depending on the light, of course. Some lights are inefficient even on low (look, for example, and most of the infinite-brightness ring-based lights -- you get an awesome UI, but at the expense of efficiency at low). And there are definitely lights where it seems all the engineering effort got put into a driver and heat sink that could support the highest highs, at the expense of tuning low-end runtimes. But of course, there are lights that have relatively more efficient lows, too

Thanks, Joe, and thanks to everyone else. It was very en..light..ening.

Years ago, a bunch of us went to the top of a mountain on the Palm Springs tram. My buddy and me brought everything we were supposed to bring, including a couple of those inflatable mattresses that are great for putting our sleeping bags on. But I was a novice. One of the other fellows was supposed to bring a couple of flashlights. This was in the early 70s and this guy had one. And it was state of the art! It was chrome plated and had two magnets on the side, and it had two silver batteries that had come with it. The price tag was $1.99...a steal.

We were a little late in getting up the tram and the sun went down moments after we got to the top. It had been warm down the tram but now a decidedly cold wind was whipping through the mountaintop. We found ourselves on a narrow trail that led through the brush and only the guy with the flashlight could see anything, and within ten minutes he had to hit it on the side to see where the trail went. We could see the flickering of distant fires off to both sides, but we had no idea where we were or where we were going. We finally found a clearing among some rocks and built a roaring fire, but we were too high and the bitter chill wind whipped around the rocks and stones around us. Then we found out these other nitwits hadn't brought cushions or sleeping bags.

It was a horrible night, but had I had one of my current flashlights, it would have worked much better. We would have found a much better place not so high...plus despite the fact that these morons hadn't prepared at all, my buddy and I didn't have the heart to sleep all night in the bags and cushions we had hauled along on the trip. I learned something that night about flashlights and I'm still appalled that hardware stores still sell crap as flashlight.

If only I had had my Klarus XT11! EagleTac's emphasis only on bright lights (plus their higher prices) makes the Klarus and the Olights much better deals in my view. My EDC is now a Klarus XTC2, which is one of the best lights I've ever bought. It replaces my Fenix L2D AA, which is a great light too...just a little long in the tooth.

Again, thanks guys. If you have any further advice or info, I'd love to hear it. Besides Olight, Klarus, EagleTac and Fenix, are there any decent comparable lights I may have overlooked?