Why Big Diff in L2/L4/L5 100 Lumen Runtimes?

From Surefire's ratings--Why is the L2 100 lumens for just 1 Hour, while the L4 is 2.5 and the L5 is 5 hours?

Thanks.

PseudoFed said:

From Surefire's ratings--Why is the L2 100 lumens for just 1 Hour, while the L4 is 2.5 and the L5 is 5 hours?

Thanks.

Click to expand...

They all run for about one hour in FULL regulation.

The new L5 has a SSC-P4 instead of the Lux V, that's it why it now has a 5-hour runtime. The older L5s were pretty much like the L2 and the L4 when it comes to output/runtime.

The L2 has to contend with the two-stage output electronics and mechanics compared to the L4 which is able to be more specialised and efficient, perhaps compromising usability though.

The L5 (KL5) has far more mass and space inside the bezel for more effective electronics and the ability to run cooler.

One thing to note is that it is better to compare actual observed performance by comparing output/runtime chart data rather than taking the simplistic ratings as read.

That's one thing that bugs me about SF is their runtime ratings. When I was shopping for my E1B (glad I got one B4 that price increase, I wouldn't pay $150) I had a hard time sorting out what they are talking about with runtimes. For some lights it's how long it's regulated, for others it's how long it's at "tactical" levels and for others it is how long it's at "useful" output. They are rich enough and do enough testing that they should have runtime plots on their website for every light that they sell, IMO. They obviously have the plots and, while they are realistic (conservative sometimes) about their lumen ratings they get a bit confusing with their runtime ratings.