I like the jax better, nicer and better quality imo, but the smaller thwart numbers, and specially the price difference (due to MAP policies, just remember that fight BG-GB…) made me go for the 1504 group buy, approx halving the (discounted) price of the jax. Even the 2 cell 1405 complete light is 5$ cheaper than the (also discounted) jax z1 host
I have the MC-E zoomie from way back when and it leaves the + sign in the die, so don't count on throw. Lumens, well, there won't be a competition to most lights on the market, even assuming it isn't driven to capacity, but that will NOT satisfy the throw-hounds out there.
My 55kcd measurement of the xml2 version converts to 469m. So they’re about the same throw, but the xhp50 should have a larger hotspot with the signature plus sign through it and a heck of a lot more heat.
Lumens and throw are mostly unrelated. For example consider a light bulb, which has high lumens and almost no lux or throw, and a laser, which has barely any lumens but has high lux and throw.
So, for throw it’s all about lux. However, double the lux still doesn’t mean double the throw. It’s a square root relationship, so four times the lux is needed to double the throw. Here are a few throw distances and the lux needed to get them:
If I recall correctly, the XHP-70 is basically four XM-L2 dies all placed together under one dome. The XM-L2 is a 2mm die (3mm apparent, with dome on). The XP-G2 is a 1.4mm die, or 1.9mm apparent with the dome. So, the math works out like this:
Two XM-L2s appear 6mm wide.
A de-domed XP-G2 appears 1.4mm wide.
The XHP-70 is rated for 4022 lm.
The XP-G2 is rated for 537 lm.
So, XHP-70 has (6 / 1.4) 2 or 18.36 times as much surface area, but only 4022/537 or 7.48 times as many lumens.
7.48 / 18.36 works out to about 40%, less than half the surface intensity.
So, going purely by numbers on Cree’s spec sheets, the XHP-70 should end up getting less than half as much throw compared to a de-domed XP-G2, despite putting out 7.5X as much light and using 6.5X as much power. Additionally, we’ve found that the XP-G2 can put out significantly more light if overdriven, so the difference in throw is probably even more.
A de-domed XP-E2 or XP-C could theoretically throw even better since they’re smaller, but in practice it hasn’t worked very well and the beam usually ends up too laser-like.
Nope.
You cannot measure the from from the total output. The throw depends entirely on the light output of the die PER SQUARE INCH/MILLIMETER.
Yes, the XM L2 reaches far mor Lumens then the XP G2, but the surface of the die is much larger as well.
In other words: the smaller and brigther the lightsource/die, the more throw you can achieve.
Just modded my JAX Z1, finally. Did a gas de-domed XM-L2 U4 1C on 20mm Noctigon. Resistor modded the stock driver by adding a R120 (an R075 produced too much current at the LED). With the R120, I got 2.8A at the tail, and ~4.7A at the LED, measured on the bench with 2 cells. I'm running two KK button tops.
I got 216 kcd measured at 5m, which is 930 meters. Distance is based on the amount of light equal to moonlight, which is 1/4 candela, so you take your candela, multiple by 4 (or divide by 0.25), then take the square root of that.