Oh, er, I forgot to mention that I normalized everything back down to a 1m reading equivalent. Pretty simple at 2m, just multiply all the values by 4.
I was a bit too busy with last-minute distro release stuff last night to take any more readings, but hopefully I can tonight since work is mostly taking a break for a few days.
Maybe I can even kludge together an integrating sphere soon. Seems like a fun project.
Oh yeah. I understood how you got your readings but I was just suggesting that becase good throwers normally take a little distance for the beam to fully collimate and your reading at 2 meters being better than the 1 meter kind of backs it up. We measure any thing over 50k at 5 meters and the really serious throwers at 15. It looks like we are getting some great lights.
I did some quick lux measurements at 5m:
Skyray King XM-L T6 1A (CNQG original): 26.9k cd
XinTD C8 V4 XM-L2 T6 3C (IOS): 37.8k cd
BLF C10: 82.0k cd
I didn’t do anything special with batteries, other than making sure they were charged recently (a few days ago, not used much since). (Panasonic NCR18650A, 3100mAh, protected… but at just 2.8A it’s probably okay to have non-high-drain cells)
The values for SRK and C8 are higher than I expected. It’s quite possible that my lux meter inflates the values a bit, or perhaps I’m getting some extra light splashed on due to the geometry of the area where I tested. In the latter case, the more spill a light has (or the wider its spot), the more inflated its value would look. I’ll have to try again in a place where spill can’t reflect onto the target.
I also have discovered other things, like that I prefer my office to be at a lux of only 10 to 20 cd while working, and ~1 cd is comfortable when I’m not reading. Comparing that to wikipedia’s reference values (100 cd = very dark overcast day, 320-500 cd = office lighting), confirms I’m a bit photosensitive. I thought 100 cd (ambient) was uncomfortable earlier today, inside with blinds shut.
Many times people that have migraines are more light sensitive, especially when concentrating such as in working in an office. Also the office might be using a fluorescent lighting that affects you negatively. Many people can't stand the lighting in an office and manufacturers are getting tuned to that, offering some much better spectrums for that very reason.
Good luck! Enjoy the C10, sounds like you've got a really nice one. (missed out on that, due to the fiasco...was going to build my own but wanted the engraving.) :(
Nope, no migraines. And I actually like the cool white lighting from fluorescents — warm-tinted lights are what hurts. I usually need cool/neutral white or wide-spectrum light.
Also, I didn’t notice until now that this lux meter has a tripod mount on the back. That should make things quite a bit easier. 
(shouldn’t change the C10 measurement much, but I expect the wider-beam lights to get lower readings when the meter is in a better place)
Could you get a beamshot? Would really like to see how that C10 is performing.
Yes, planning to do beam shots comparing it to a C8 and SRK.
(just not quite sure where yet, since I haven’t tried beam shots of this intensity before)
Actually even on a light like this C10 you will see an increase of quite a bit with fresh cells and higher amp batteries will give you even more. I would expect with fresh High amp Batteries to see triple the C8. Possibly more.
I just did a quick reading without going outside to check or even calculate distance. (just across part of my living room) My C12 from lightmalls that is supposed to be their highest amp stock driver and XM-L2 was 28 The C10 that I did just like yours but with high amp batteries showed 115. So closer to 4 times.
Fresh panasonic 3400 was 91. Fresh off the charger trustfire was 78.
I fully intend to drink a bottle of red wine and take a few photos tonight.
But I’m having an idea where the camera is out at the 500 yards, and take the photo in the area the flashlight is lighting up. I’ve wanted to do this with a wicked laser forever now… be standing in that green dot out a mile away where it’s landing you understand what I mean? Be standing in the dot, instead of taking a picture of it from the laser holder’s point of view.
Might have to give that a go my own self! :)
Thank you for the C10 and parts! I haven’t gone outside with it yet. We had fourteen inches of snow yesterday morning. J) The tint is warmer, more yellow than my Xin TD C8 V3 T6 3C. The hot spot is smaller and tighter than the Xin TD and smaller then the Jacob A60. Here some tail cap measurements.
Xin TD 2.71
C10 1.96
A60 1.83
Thank You Again
18sixfifty, it seems you’re quite correct about the batteries. I measured the one I had been using and it was only pushing 1.8A. I tried another and it got about 2.3A. I suspect my DMM leads may not getting enough contact to be fully accurate here, but regardless, it’s an improvement. And this is a great excuse to get some higher-amp batteries soon too.
I re-tested in a better location (not prone to spill artifacts) with a better battery, and got results much closer to what I initially expected — 21.9 kcd SRK, 32.5 kcd XinTD C8, 84.0 kcd BLF C10. (my guesses before measuring anything were 22, 33, and 90… so I was pretty close)
Now I’m getting everything fully charged so I can test a bunch of different lights and get more accurate numbers. With any luck, I won’t get any questions from my partner about why there’s a light meter on a tripod in front of the bedroom’s black-out curtain, with a tape measure leading from it out into the hallway.
(edit: with fresh cells, make that 32.8 kcd for the C8, and 88.0 kcd for the C10)
Which High amp battery would you recommend and would no protection circuit help even more
Unprotected cells should definitely handle higher amps than protected cells of the same type.
However, as for what type to use, I was planning to go to RMM’s store and get some high-discharge Efest batteries. Looks like he might not have any in stock right now though. Regardless, I need to get a couple high-amp 18650s and a couple high-capacity 18350s.
He has the 20R’s in stock and I have not seen anything beat them yet. You can not go wrong with either. Nor with the 25R’s.
The 20R is the top dawg for amp delivery, and the 25R is excellent as well with higher capacity.
If y'all have stock drivers, the driver is going to limit your amperage to 2.8 or 3.04 or whatever, not much point in using the ultimate cell if you're not using the ultimate driver. Most any cell out there will easily fill the bill for 2.8A.
With the regulated drivers, the only way a better cell will help is if you're not getting the amperage the driver is rated for. Even then, you'll only see a marginal gain from the high discharge cell...the driver is not letting more amperage through by design. If it's got 8 7135 regulation chips that are 350mA rated, then you're going to be stopped at 2.8A regardless of what cell you use. If the chips are binned at 380mA, then 3.04A should be the maximum the driver allows. Stack some chips and you'll get more. Until then, more expensive higher discharge rate cells are not going to be the do all end all with these drivers.
Yow. Note to self: Once a light is focused, never touch it again.
I took the reflector off for a quick test with an aspheric, and now I’m having a difficult time getting the bezel screwed down without de-focusing it in the process.
The good news is… I should be able to pretty easily get my UF-838 up to 60kcd of lux with nothing but a star/emitter swap (and some extra heat sinking if I can find fitting parts).
I also received two modded C10s. Unfortunately I’ve found some issues with them.
One of the lights was not working at all.
The other one was working but the LED was not soldered straight to the sinkpad.
Here are some pics of the lights and how I fixed them:
First light
Not working at all. I found that there is not enough solder under the emitter.
pill removed
testing LED with a meeter
LED removed
added some solder before reflowing the emitter
Second light:
not straight emitter:
(+) and (-) swapped:
I think that other people need to double check how well the LED is soldered to the sinkpad.
Sorry to hear you had trouble. When they left here they were working fine. I tested each of them before shipping. I wouldn’t send out a light that I hadn’t tested. I have re-flowed hundreds of emitters now and I prefer to use as little of solder as possible although I don’t bother making sure I put them on the correct way when it comes to positive or negative. I check them after I re-flow them and again before I solder the wires on. I also tested each light on my light meter to make sure that I was getting roughly the same Kcd out of each light.
I really can’t see how they could possibly have come un-flowed. I not only tested each light before I sent it out I checked each to make sure that I got the emitter centered in the middle of the light itself, On a light like this getting it perfectly centered is difficult and takes a few tries to get them right. I don’t suggest anyone take a light apart but I’m glad to see you managed to get them running the way you wanted.
If the emitter isn’t centered correctly in the reflector there is no way I can get the lux numbers correct either, plus you just won’t get a hotspot to look right.
Again I wouldn’t suggest anyone take their’s apart unless you know what you are doing. One bump of the wires on the de-domed emitter and it’s shot, Not to mention getting them back in focus is difficult to say the least.
It is a pity that not all types of needed centering rings are available, with various diameters and also of various thicknesses, including very thin ones. Especially for 3535 emitters they are scarse. There is more variety in xml-sized rings, while especially the dedomed xpg's (and xpe's) are the thoughest to align. And the C10 reflector has an especially large hole making centering by eye even more a trial and error job.
About using as little solder as possible (including the use of a solder stencil for reflowing leds): my recent tests of 20mm boards suggest that the thickness of the solder layer under the thermal path of the emitter has a negligible effect on the thermal performance of the led, since then I do not worry anymore about my habit of using ample solder paste ;-)