Headlamps with constant brightness regulation?

[ToddM]

So it seems these days most companies are just using regulation to pad their brightness/runtime numbers. The ANSI FL1 spec is a joke, pushing us back into the flashlight stone age where lights were only bright for a few minutes. Some companies have their super bright turbo mode where they either mislead the runtime using the FL1 spec, or simply say the runtime is the brightness + runtime at a lower brightness. Letting them basically turbo the light for 1 minute and then step down to a much lower brightness and calling that the runtime for the turbo brightness. The issue becomes in many cases the company doesn't tell you if they are using the FL1 spec to mislead consumers on the runtimes for their high/med/low runtimes as well.

That rant aside, what headlamps today offer constant brightness runtimes in their specs? Where regulation is used for what it should be, to offer maximum constant brightness over most of the battery life. Surefire used to have a "tactical" runtime where it was the runtime at 90% of initial brightness but it appears even they don't do this anymore. I don't mind if they play the FL1 game with their turbo modes, but I definitely want flat runtime/brightness curves on the high/med/low settings where they are trying to create a constant brightness over the vast majority of runtime.

 

[Lynx_Arc]

Turbo is akin to Turbo on cars the mode isn't for continuous operation when it was first put on lights but rather for a short burst.
Cheaper lights that are designed with using alkalines don't have regulation as they are less able to hold output steady so instead of having a 500 lumen mode and a 150 lumen mode and run at a slowly fading 500 lumens till it hits 150 it would step down to 150 when it cannot keep at 500 lumens so runtime at a fading 200-400 lumens would not be there only very bright then adequate output. Rechargeables are more able to maintain a flatter discharge curve so you can have decent runtime on high then step down to lower modes. I agree that something should be done about Turbo advertising and the ANSI FL1 idea is better than nothing but doesn't favor the consumer at all with LED technology whoever decided runtime goes down to 10% was foolish it should have been something higher like 50% or around there.

 

[ToddM]

To me even 50% is unacceptable, if I need 100 lumens to do a task, 50% is a huge drop. I'd say 80% at the least, but the reality is the spec was designed from the ground up to mislead consumers.

I suppose it depends on the use case, if I'm only using the light for a couple minutes at a time it's not a big deal, but if it's continuous use I want a light that maintains that brightness for the bulk of the runtime. I'm even fine with a "turbo" mode that has to step down for heat etc. to get a short lived super bright blast, but for High/Med/Low I want as much runtime as I can get but with the brightness maintained. There's no point to have a 500 "high mode" lumen headlamp that in 15 minutes is really only 100 lumens. Especially for a headlamp, it's rarely something you are only using for a couple minutes here and there, it's almost always something you are using long duration, hiking, biking, construction, vehicle work etc.

If it was up to me the FL1 spec would be the exact opposite of what it is, 90% brightness maintained not 10%. We could stop having products misleadingly marketed as 1000 lumen headlamps that are only 1000 lumens for 45 seconds.

 

[WalkIntoTheLight]

Zebralight is regulated, up until the point the light gets too hot, then it will adjust brightness to keep the temperature below the threshold. If it's cool outside, or you grip the body tightly to act as an additional heat-sink, that will keep the light at max brightness until the battery is drained.

If you use the light a step or two below max, then usually the light never gets hot enough for thermal regulation to take over.

 

[AstroTurf]

One more vote for Zebralight headlamps!!!

 

[Swedpat]

ToddM:

I agree with you that ANSI FL1 specs is a joke. It actually gives manufacturers justification to give deceptive specifications.
And I like stable output. But regarding what you thought about that 50% is unacceptable: yes, if the specifications states regulated output for constant output, a 50% drop is simply not true. But still I dare to say that a halvened brightness is not that big as one could expect when the decline is gradual and slow. In many cases it needs a 50% drop until you start to suspect it has started to be dimmer!

 

[Lynx_Arc]

Most decent headlamps with a Turbo the H/M/L modes are for most decent driver designs are regulated as the heat generated is not beyond the capability of the light to handle. It often is when you are running a lower power battery solution that the high and turbo modes are short lived as the battery just doesn't have the power to sustain the current draw. This is why I went to 18650 based headlamps as the sustainable output of 1-2 AA headlamps was insufficient for me either I got decent lumens in the 100 lumen range with unacceptable runtime or acceptable runtime with lower than acceptable lumen output. If you drop the battery size to 14500 your runtime vs an 18650 is a lot reduced. Typically you want to look at lights that have the output you desire and check actual reviews with graphs even so the runtime and lumen output is easily verified.