It’s a slightly bigger light, and its highest mode without thermal regulation is 312 lm. So, I’d say the D4’s ~600 lm steady state (at a moderate thermal ceiling) is pretty fair. If you want it brighter though, you can still set the ceiling higher or give it a better heat sink. It’s funny to watch what happens when touching a block of ice to the D4. Even just getting it wet makes a huge difference in the level it stabilizes to.
Some are trivial, others are not. I’m working on some new code to make all these things trivial, and to make new UIs easy to create, but it’s not ready yet.
After getting the different current readings on my 20700 fitted D4, I changed it up some. The tube threads at the head are pretty short, so I moved the copper spacer to the tail end and made the necessary adjustments for it to all work. Now, with a better ground that is consistently repeatable, I’m seeing 17.6A out of the freshly charged Sanyo NCR20700B cell. This allows for 3915.75 lumens out the front, at start. The 219C is a greedy emitter, it’ll take whatever you give it, up to a point.
I charged up and tested one of TomE’s Sanyo NCR20700A cells, wow! 21.14A at the tail for 4391.85 lumens from the Emisar D4 with Nichia 219C emitters. Yowza! Do it get hot? Is it noisy at Mardi Gras?
That’s basically how the thermal calibration mode works now.
The sensor is not at the emitters though. The sensor is behind the MCPCB, the shelf, and an air gap. Its measurements are rather lagged, which is the main reason it’s difficult to steer. Putting the sensor directly on the MCPCB would make things much easier.
Infrared thermometers are cheap and good for various things, like cooking. For longer range measurements, look for a bigger distance to spot ratio. Otherwise 1:1 ones can be had for a few bucks shipped.
Thanks for the reply on the SC600. Mine is the Mk II cool white, so H2 is still around 670. No matter though, thanks for the confirmation. Still this D4evil is impressive.
yay my own D4 finally came, waiting over the weekend was bad at least the wait is worth it.
This things heats up nearly instantly just crazy, the light output is kind of underwhelming first and it is daylight here so i cant test it outside then i ran ceiling bounce test it was at least twice as bright as my Astrolux S41 wow!, i guess the eyes perception doesn’t work in linear manner.
This flashlight is really small i cant imagine it is being that small until you have one in you hand. I like the plain tube, with all the flashlights available in the market this look different and feels smooth, and the green is also beautiful i didn’t regret it. Cant wait for the sun to sets.
Can’t overlay the output on the video, but here it is on the graph.
Interesting how fast the VTC6 cools down because of the immediate stepdown and the Aspire just keeps getting hotter because of less thermal mass with the 18350 tube. I’ll probably measure the temp for a longer time to see where they stabilize.
Now, I can’t be sure which one of my seven Aspires I used on the thermal image, so it might not be the same one. Here’s two of the best samples compared and even they differ greatly because of different internal resistance.
i actually prefer the D7 or D6 if exist to run on 20700 instead of 26650. 20700 or 21700 is where the battery technology is currently being pushed further.
I wish for 21700 D4. With bored tube 20700 fits already. A slight size increase and it would take 21700. There are no great 21700 batteries available now, but this format really seems like the future.
Battery size increase would give us 5000 mAh with current 18650 tech. And with nearly the same flashlight size.
Try to make sense of the rainbow, but there’s not much difference in output between good batteries. The individual cell samples are probably just as different.
I saw a news release the other day where Yuasa in Japan announced a breakthrough in Lithium-ion cells that will be giving much more range to electric cars by 2020 or earlier. Didn’t see specifics… change is coming though.
