Source: Alibaba : Shenzhen Kechuang Fire Technology
Sample Price: $75 inc. shipping
Box Contents: Flashlight, charger, 2x batteries
Packaging: Brown box, safety stickers on batteries
Switch Type: Magnetic, gradual
Battery Type: 32650 (claimed 5000mAh, not tested)
Claimed Lumens: 5000
Measured Useable Lumen Estimate: 1800 usable, 4000 theoretical
Shipping time: <7 days
Review:
Today I’m reviewing a light from KC Fire in Shenzhen – based on the XHP70 diode, this should be fairly bright.
At 1m distance it throws two cones of light (all measurements taken in a dark room with <2lux background light).
Inner cone: 17-20cm diameter (i.e. 10degree beam), average lux 29160 (5 readings) – peak 37000 (remember lux, NOT lumens)
Outer cone: 150cm diameter (i.e. 74degree beam), average lux 651 (8 readings) – peak 720 (remember lux, NOT lumens)
So…. after some simple math, the 17cm cone has around 660lumens, while the 150cm (dimmer) cone has 1137 lumens at 1 meter. Even taking the inner cone as 20cm instead of 17cm, we are still only looking at 998 lumens (total around 1800 lumens, useable).
1m behind the flashlight (pointed at a matt white wall), I get 200lux readings and about 77lux 5m behind the light. Importance of this is that lumen output from a flashlight is meant to be measured in a sphere around the light, not just on the flat surface it’s projected against. So with a sphere of 1m radius (2m diameter, 6.28m surface area), and assuming the light pumps out 200lux all around – we are looking at 1256 lumens. So if we counted this, we would go up to 3959 lumens (total).
Build quality seems pretty good – some decorative screws holding the rubber handle in, 2 o-rings on the screw back cap. Front lens is recessed, so should protect it from some scratches. Feels like glass, but can’t confirm. After 4 minutes powered on, light feels distinctly warm. Don’t have a FLIR to hand, so can’t tell you how warm sadly… may borrow a flir from work and test (in the meantime, I may put the light in a cold water bath).
In terms of subjective brightness, it feels quite a bit brighter than my previous Chinese CREE light… but as that flooded when I forgot to put the cap on, I can’t test (currently hopeful that it comes back to life). Whether the light is any use diving is another story…
I’ve now “tested” this subjectively against my dive buddies green force travel light. The beam angle and power feel similar, with a little more scatter on the KC Fire light.
As for duration… ended up falling asleep it took so long to get the batteries flat. When I woke up 5 hrs and 30 minutes later, it was still powered on, albeit substantially dimmer. If there’s enough interest, I’ll plot a lux-vs-time chart; btu the point is, duration is easily good enough for a few dives.
After putting it through a set of charge/discharge cycles using the provided charger, one of the two bays on the provided charger stopped working (<10 cycles), but the batteries seem to charge on the second bay (one at a time).
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