Assuming that the current can be used as proxy of the battery discharge rate, it’s a Power regression to a tune of: y=6.3x^0.62. Not surprisingly, this means, given the nonlinear perception of brightness, large increases of current and therefore power and therefore large chunks of battery life may be needed to achieve relatively modest increases in brightness.
Keep it low, and enjoy the light for much, much longer. For example, moving from 250 lm to 1000 lm may be perceived as doubling the brightness, but it would result in some 9 times shorter battery life (and given that battery capacity normally decreases at higher currents, possibly shorter).
If the perceived brightness is assumed to follow inverse gamma function (lumens^0.45), then this disproportionate power consumption increase with increased brightness at the higher end can be seen even better:
That Turbo at 1000 lm may look a tad brighter than High at 550 lm, but it requires some 3 times more power to do that. May not be worth it.
It coincides well with practice: Turbo on SC11C looks just a little brighter than High, but draws are 1.25A vs. 3.7A. The real value of Turbo is that it can be entered momentarily with double-click from anywhere.
Still a big difference in throw. Both battery at 3.85v.
I think most of the difference comes from the optics. FC11C has standard profile OP reflector, SP31V3 has deep profile throwy clear TIR. Most of the light would be gathered to form the hot spot and it has dimmer spill.
When I got my FC11C a few months back I did some run time testing using my Vapcell F14 18350. I might pick up a few of the new H16 cells and re run the test in the next few months. Overall I have been quite happy with the runtime and efficiency.
I was very impressed with the results, Brightness is somewhat arbitrary as I was using an older Extech Light meter adapter for a DMM hooked up to a Mooshimeter to do the datalogging. I’m also pretty sure I already had DC fix on the light when I ran the test
All new models of buck driven lights from Wurkkos and Sofirn are very good with efficient driver and flat regulations. It’s a trend that I’m happy to see.
To answer the questions regard to SP31V3’s UI, the tail clicky has no delay and will light up the LED immediately. I have Acebeam L19.2 so I am familiar with Acebeam’s implementation of electronic tactical tail + side switches. The sofirn works differently as the tail is mechanical rather than electronic like the Acebeam. They are two different UI with their own pros and cons.
For EDC I find Sofirn’s tactical UI more convenient, as I can half press the tail to light it up for a quick inspection without it blasting turbo to blind everyone. With a reverse grip of the light, the pinky can reach the side switch. So you can still one hand operate it without having to change grip.
Does your FC11C go into moon mode, and moon mode only if the head isn’t cranked all the way down?
Literally got mine yesterday with the intention of using the 18350 body, but it seems to not even be making contact with the stock body. Cleaned the negative battery ring, and the only way to get mine to work is to tighten it beyond a reasonable amount. Maybe there’s a broken solder joint somewhere.
I like the dual switch UI of the sofirn. I grew up with tail switches, and I’m curious if there’s any 18350 solution for it
No, mine works fine. I’m using Wurkkos short tube. Some short tubes, like the original one on IF19, are not the same length. Not sure what it is. Sometimes it feels tight because the o-rings no longer have silicone grease on them but it’s the rim of the tube that needs to contact the cap or head. If there is no contact Moon shouldn’t work either.
Maybe that’s the issue. For the rim of the tube to make contact with the cap or the head, it has to be tight, as in when the rim makes contact with the rest of the light, you won’t be able to tighten it anymore, even a little. Why the Moon would work but no other modes, remains a mystery, but it doesn’t look like the bad contact issue.
If you could make a short VDO of how the light reacts to your maneuvers, I’m sure somebody would come up with a diagnosis.
I don’t have answers to @Garageboy’s predicament, but something similar happened to me today. The FC11C after recharging decided to work only on Moon and Turbo. Couldn’t change brightness at all. Other functions such as strobe worked. Changing/removing batteries did not work. Then, suddenly, it started working again.
Not sure if this is even a thing, but is there a way of rebooting the Wurkkos firmware light somehow if something like this happens again?
As @Lightbringer lamented - what was wrong with a nice mechanical switch of Maglight kind that didn’t have moods? Or a rotary knob if one insisted on light levels.
Not sure how to interpret it. ZeroAir reviewed the 4000K version of this light, 1Lumen the 5000K model. They both measured tailcap currents at each of 5 modes at start, which, unlike lumens, should be relatively simple to measure and have little uncertainty.
Even if there is a Vf difference it shouldn’t be that large. I suppose it’s just the way they test it which have a lot of variance.
The firmware might adjust for different models of LED, but I doubt they even adjust for different tint / CCT bin, too much hassle.
The SP31V3 manual lists two different output and runtime tables for SST40 and 519A. So the output is definitely adjusted according to the LED model. Since both have medium output of 300lm and different runtimes, which is still a bit dubious because they list SST40 at 5:50h and 519A at 6:10h, which seems impossible because 519A can’t possibly be the more efficient one?!
Not sure if this is reproducibility issue - e.g. @SammysHP measured currents for the 5000K version and reported virtually the same values as @1Lumen . Not sure if somebody else did it for the 4000K to compare with @zeroair values.
You can’t measure current with a multimeter if the device under test depends on the voltage. The multimeter adds significant resistance due to the shunt used for current measurement. This will limit the performance of the flashlight significantly. At very low currents the difference is small because of the smaller voltage drop.
Also there are multimeters (hobbyist level) capable of measuring currents up to 20A. I guess they have much lower resistance shunts and provide acceptable accuracy in ranges up to, I don’t know, maybe 7 amps.
No, because even those “regulated” modes depend on the full voltage of the battery.
While they might have a low resistant shunt, they still introduce a voltage drop. If you want to measure more than let’s say 100mA, you need a clamp meter.
Oh, I do have a clamp meter. I bought it to measure dozens and hundreds of amps so don’t recognize it as a valid meter for low currents :).
Retested high and turbo modes with clamp meter, updated my earlier comment with new results. But actualy clamp meter seems to be pretty inaccurate in ampere units range, not to mention milliamps ( at least cheap ones).
