The math doesn't work here

[KingGlamis]

Looking on SureFire's web site the G2 LED is rated at 80 lumens for 12 hours and uses two 123A cells. The G3 LED uses THREE 123A cells and is rated at 80 lumens for 9.4 hours.

Say what? Same lumens, add a battery and the run time decreases? They don't list which emitters are used but with the same lumen rating it's probably the same one in each light. What gives?

 

[PsychoBunny]

Typo!

 

[RobertM]

The G3L stays in regulation longer, and accordingly, has less time of diminishing output.

There are some runtime graphs floating around here depicting this.

-Robert

EDIT: Here they are:

Ok, onto the G3 series. Here is the G3L with the P60L LED on Surefire Primaries.

A good general purpose light. Regulated runtime was spot on at just over 5.5hrs with an additional 2hrs of usable light after falling out of regulation.


C.P.T.

I'll post one more for tonight and give the Mods time to approve them.

Here is the Surefire 6PL with the P60L module on Surefire primaries.

The 2008 Surefire catalog states 11hrs runtime on this light, but I think that's until exhaustion. As you can see, I got almost 4hrs of regulated runtime and then shut it off at just over 5.5hrs at 500Lux. It might still have been lit at 11hrs but I don't think I'd want to try to navigate with it.

Has anybody measured longer than 4hrs regulated runtime on one of these?

Later.

C.P.T.

 

[Kestrel]

SF unfortunately claimed runtimes for the G2L and the 6PL for an output down to ~1 lumen. With all of their other modesty, I find this very disappointing. To add insult to injury, the only reason that they claim an additional 1 hour for the G2L is that the thermal regulation (which is simply burning off excess power) throttles the "80" lumens down to ~60 instead of ~70 for the P6L. They are claiming extra runtime in the Nitrolon body (holds more heat, more thermal limiting), but are not admitting that the output is decreased at all! Pretty cr@ppy.

And their description of the G3L's performance is even inconsistent with all of this!

 

[Gunner12]

One is till 1 lumen(G2L), the other I'm not sure(G3L).

 

[Marduke]

SF is quoting LED Lenser runtimes here, not regulated or 50% runtimes.

 

[SureAddicted]

The way major manufacturers quote runtime is where there is practically not light coming out of the front end. Fenix, SF, Jetbeam, Nitecore, LL, et etc all measure the runtime the same way, or similar, and this is till the battery source is depleted, or close to it. It's how things are done, take car manufacturers, they dont quote mpg to half a tank, that would be silly, its till there is no juice left in the tank. Electronics companies who use prorprietory or regular battery sources quote runtimes the same way, ie kodak, sony, canon.etc etc.
I've never heard of a company quoting runtime to 50% and I doubt that I ever will.
In regards to the G2L & G3L, the G3L has the advantage of holding a brighter level of light for a bit longer over the G2L. Both suffer from thermal management heat issues.

 

[Kestrel]

The way major manufacturers quote runtime is where there is practically not light coming out of the front end. Fenix, SF, Jetbeam, Nitecore, LL, et etc all measure the runtime the same way, or similar, and this is till the battery source is depleted, or close to it ... I've never heard of a company quoting runtime to 50% and I doubt that I ever will.

I think that most other SF runtimes are pretty honest, especially with regards to their underrated outputs. _Usually_, when they say 80 lumens, it's 80 lumens at ~50% discharge, and this calculation actually tends to make their runtimes look better by the same math. From what I read on CPF at least, FWIW, YMMV.

 

[Marduke]

The way major manufacturers quote runtime is where there is practically not light coming out of the front end. Fenix, SF, Jetbeam, Nitecore, LL, et etc all measure the runtime the same way, or similar, and this is till the battery source is depleted, or close to it. It's how things are done, take car manufacturers, they dont quote mpg to half a tank, that would be silly, its till there is no juice left in the tank. Electronics companies who use prorprietory or regular battery sources quote runtimes the same way, ie kodak, sony, canon.etc etc.
I've never heard of a company quoting runtime to 50% and I doubt that I ever will.
In regards to the G2L & G3L, the G3L has the advantage of holding a brighter level of light for a bit longer over the G2L. Both suffer from thermal management heat issues.

Most honest companies quote regulated runtime, or runtime to 50% (virtually identical) , because that corresponds to the most useful level of light for most consumers. That does not mean you are ignoring 50% of your battery life, as by the time a light reaches 50%, you are at the end of regulation, and entering moon mode. Runtime to any value between 70% and 10% is usually within minutes of eachother on a regulated light, so that aspect is a moot point.

The dishonest aspect comes in when companies quote the END of the moon mode, and that is the issue here.

 

[Bushman5]

I think that most other SF runtimes are pretty honest, especially with regards to their underrated outputs. _Usually_, when they say 80 lumens, it's 80 lumens at ~50% discharge, and this calculation actually tends to make their runtimes look better by the same math. From what I read on CPF at least, FWIW, YMMV.

I have always found that SF overrates their claimed output..... :thumbsdow that being said i still like them and am planning to buy more...:twothumbs

 

[Kestrel]

I think that most other SF runtimes are pretty honest, especially with regards to their underrated outputs ... and this calculation actually tends to make their runtimes look better by the same math ... YMMV.

(Emphasis added)

(i.e. runtimes to 50%)

I have always found that SF overrates their claimed output

SF E2DL:
Surefire website: 120 lumens
"Actual Lumens readings in 6" dia. Lab Sphere IS with SC 5500 control" thread:
SureFire E2DL on high,________210__turn on___________2 primaries__________Brand new as is from Factory!
SureFire E2DL on high,________203__warm.____________2 primaries__________let it run over a minute,

6P:
Surefire website: 65 lumens
Actual lumens reading:
SureFire P60 Lamp__________80___turn on peak______2XCR123__________Solarforce L2 Host, non crenellated Bezel!
SureFire P60 Lamp__________68___warm___________2XCR123_________ __Solarforce L2 Host, non crenellated Bezel!

6PL:
Surefire website: 80 lumens
Actual lumens reading:
SureFire 6PLED_______________82,__________________2 primaries__________original LED________,

M600C scout:
Surefire website: 120 lumens
Actual lumens reading:
SureFire M600C Scout,________171__turn on___________2 primaries__________KX2C head; single mode version of the E2DL,
SureFire M600C Scout,________165__warm.____________2 primaries__________60 second warm up time.


SureFire's measured output numbers are looking pretty darn good to me, compared to their claimed values. If you could provide a reference for how SF overrates their claimed outputs, I'd like to read it.

Quotes taken from MrGman's thread,
http://www.candlepowerforums.com/vb/showthread.php?t=211402

 

[Marduke]

Output rating :thumbsup:

Runtime rating :thumbsdow

Reliability of clicky switches :thumbsdow:thumbsdow

IME, YMMV...

 

[Benson]

The way major manufacturers quote runtime is where there is practically not light coming out of the front end. Fenix, SF, Jetbeam, Nitecore, LL, et etc all measure the runtime the same way, or similar, and this is till the battery source is depleted, or close to it. It's how things are done, take car manufacturers, they dont quote mpg to half a tank, that would be silly, its till there is no juice left in the tank.

That would be silly (especially because mpg has no relation to fuel tank capacity; I'll assume you meant range), but has no relevance to this for two reasons:

1. You're talking about 50% of energy capacity, we're talking about 50% output. If when a car ran low enough on gas, it could only go 50% the speed, or 50% the power, as on a full tank, rating it to that cutoff would be a reasonable option, but cars generally make full power until the fuel pump starts sucking fumes, at which point they stall. We aren't advocating measurement to an arbitrary point of battery consumption, but to a dropoff from normal performance.
2. When a regulated light falls out of regulation and drops to 50% brightness, it has used almost all the energy in the cells -- you can sometimes get outrageously long times with the small fraction of energy left, but only because you're using at at a much lower rate. Actually, the 50% output point for cars could be defined; it would be a point when the last fuel in the rail is being injected, and 3 of 6 cylinders have lost combustion. Manufacturers generally rate it sooner than the 50% output criteria, or even the out-of-regulation criteria (when the fuel pump first sucks fumes), to be conservative and allow for variation in production -- maybe they wouldn't need to, if cars could run an extra half-hour on fumes, but they sure wouldn't rate it to the end of the fume runtime.