The readily available driver are the ones that used to drive the XHP35’s, but it’s only driving the LED at 1A so you would be seriously underdrive these LED (though not necessarily a bad thing).
On the other hand, these are 40w LEDs so running these on full tilt in flashlights with poor thermal dissipation could very well be a recipe for disaster.
I should be able to at least do a proper beamshot and side-by-side comparison against CREE’s on a flashlight this week, provided I won’t destroy the driver.
I could always let Djozz chime in later. Djozz’s result should turn up next two weeks.
Also, the manufacturer seems quite confident about CRI values of this thing. They did said something along the line of “see it for yourself”.
I got beamshots too. Unfortunately, I only have one high drain 18650, and my setup trips the overcurrent protection of other batteries. I can only give you the individual beamshot for the moment.
All the shots are taken at 5500k WB. I took this with a smartphone camera which annoyingly messes with the exposure setting.
XHP70’s Beam shot
FC40’s Beam shot — Again, This looks much less green than XHP70’s 90CRI, but a bit cooler.
Additionally, the H2-C I ordered are not the same. One of them operates in 1-mode, the other operates in 5-mode. Annoying, but it’s only the best shot I have at this. I probably don’t want to go through the trouble of sanding down the driver and coat it with nail polish again.
The nail polish coating isn’t perfect and there might be some low-key shorting which prevents the driver from pushing 1.5A, or prevents the driver from entering the turbo mode. Which I will figure out the way to measure the tail-cap current draw.
I might have overloaded the luxmeter and it stops scaling properly past 100k lux (which is it’s stated maximum range, although it continues to register the brightness over 100k lux anyway). I might try to test again from further distance and see what happens.
75 cm is likely still too close. The main reason is that the beam is not fully collimated at short distances. I’m not sure what is the minimum good distance for C8 but if you can measure at 5m I think that should be enough.
Also, what you measure is not output but intensity. I’m nearly sure that at the same intensity XHP70.2 has much higher output.
Correct Agro, a minimum 5M throw distance should be observed for Standards.
On lights I’ve built with a mile or more throw capability I use 50M for testing. If you have the light focused for optimum distance, the V shape of the beam profile hasn’t come together at closer distances and the meter isn’t getting the concentrated light to show the true throw reading. After getting lights that throw a mile or more, I can’t think of a couple of hundred meters as being throw, gonna take 3/4 of a mile or more to consider it “throwy”.
I received the two samples yesterday, but need a few days for the test because life is quite in the way this week, no spare evenings in my cave behind the cupboard at least until the weekend.