With a single cell I’m afraid you won’t see a lot of current gain as these buck drivers normally have fairly high resistance. You need to try using two batteries instead to see the increased current to the emitter after the resistor mod.
The stock driver may not be easy to pimp out for single-cell use, but this host works very nicely with a BLF22DD driver.
Also, does anyone know of a cheap plastic cover which would fit this to protect the optics? It’d be nice to carry this in a pocket without scratching the glass or the AR coating. I’m thinking something like a shallow end cap, perhaps even usable as a diffuser, roughly the shape of a petri dish.
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.