Lumintop BLF GT94 ( 4 x SBT90.2, 1.65mcd ) NOW AVAILABLE @ Neals: code NDGT94 gives $ 150 off

There is some #'s from a good source showing a 26% bump in candela for swapping an OP to SMO, Matt Smith (VOB) with a Convoy L6 XHP70.2:

Matt's vid here: https://www.youtube.com/watch?v=TRp8WxJsivw&t=213s

130 kcd to 164 kcd which is a 26% bump, but think the variations from LED to LED, light to light, reflector to reflector is significant.

Yeah, that is a bit of an outlier in my testing, I think that the combo of the XHP70.2 and the VERY heavy OP on that reflector played a role in the results.

Still, I would not be shocked to see 15-20% gain in lux with a SMO reflector in the GT94 at the cost of the slight donut hole returning.

I will have mine Monday or Tuesday. Will do the test.

Mine has Oranges in the reflector…IS THIS NORMAL…LOL…i havent got it yet…still says returned to sender…

I’ll have mine tomorrow.

Are we going to have to request the smooth reflector or is Neal just automatically sending them out to all of us who got the first batch?

We should know more once the reflectors are made but I am guessing they will be sent automatically but don’t quote me.

Wow! Can you tell if the beam is emitted from an SMO or OP reflector 1km away? Maybe because the OP reflector emits a weaker beam?

Are you sure? I don’t think the driver allows you that

It will definitely allows you. I did disable the temperature controls on my GT, GT90 and GT4. Will do my GT94 as well later today. The courier will drop it off in the next two hours.


Just received my BLF GT94

OP reflector.

Measured at 10 meter throw

1.4Mcd

1.416Mcd

BLF GT4

563Kcd

Acebeam W30

1.431Mcd

Measured at 20 meter

1.396Mcd

BLF GT (CW)

Measured at 20 meter
1.116Mcd

I designed the driver (and TomE did the firmware), pretty sure it allows you to recalibrate or disable the thermal control :wink:

It explains how in the Narsil instructions.

at 1km you will not be able to tell much as it is hard for most human eyes to even see that far clearly.

Although my statement above was a more general opinion I hold, there are exceptions to it of course but in general I pick the OP reflector when available.

In this lights case the SMO reflector has a slight donut hole (simply due to how large the die is on the LED, not much you can do about it). I am guessing the OP reflector would basically eliminate this which would be nice for everything except max range usage IMHO.

The GT94 page says it uses NarsilM and Anduril, so was wondering...

Yes, with NarsilM, you can disable thermal mgt completely.

lol, didn’t see that anduril part before, pretty sure that is just a copy/paste error.

It uses the exact same firmware hex file from the GT70, just on a beefed up driver. So Narsil 1.3 IIRC.

I read in some reviews that the GT94 gets hot very soon. Perhaps the step down set by the factory is to prevent the driver from getting damaged. Buck drivers are delicate. Perhaps it is better to leave the factory settings which has some good reason.

It's not a buck - LED's are wired in 4S, ref here: https://budgetlightforum.com/t/-/63210/46

I'm sure it's 2 channels, with the high power channel being a FET. Voltage divider resistors used to monitor battery voltage.

With 4S LED's, amps should be in the ~20 range, instead of ~80 range if they were in parallel.

I haven’t seen a donut hole in the videos posted on Youtube. Perhaps it is very light and can only be noticed by projecting the beam onto a white wall at very short distance.

I set the default step-down temperature at 55c in the firmware. Due to variances in the MCU’s this can vary by 15c+ from light to light. So the step-down could happen between 40c and 70c depending on your particular light. This is not a problem since the user can recalibrate the temperature to their liking.

The factory did not change the temperature setting from what I set it to, it is just simply variances in the MCU’s. It is perfectly safe to raise the tempreture or even disable it. The internal components are rated for 105c+, the cells are the only thing you really have to worry about, VTC6’s are rated for 80c but lower quality cells can be rated for less.

In my stress testing with thermal control disabled I saw a max temp or ~95c at the head and the cells were ~75c. So still safe even with thermal control disabled, although it is not recommended to do that on a regular basis.

In a nut shell, you are welcome to re-calibrate the temperature control to whatever temp you want or disable it completely. It is easy to do in the firmware, I simply don’t have it memorized. It should say in the manual how to do it though. If not there is a cheatsheet in the GT70 thread that has it for sure.

Correct, it is the same driver setup as the GT70, a resistor bank for the low modes and FET for the higher modes. The GT4/GT94 driver is just beefed up a fair amount to handle the ~30A it has to deal with.

I doubt a camera would pick it up easily, it is faint but there. I mostly noticed it when getting lux readings, the numbers were higher at the edge of the hotspot then in the center. It is most noticeable at mid ranges.

I am a technical guy though so I focus on things like that more then most. On the flip side I don’t generally care much about cosmetics and that sort of thing.