That is about 152kcd for 4100lux at 20ft. Better than DX80 by 50kcd if I remember correctly.
Not sure if you can fully visualize the issue. The MS12 flashlight head has a diameter of 5.1” or 20.4 in2 whereas his TA Lumen Tube can only measure up to 3.5” diameter or 9.6 in2. Therefore the TA Lumen Tube cannot capture all the light from this flashlight.
Additionally, after the whole ordeal of calibrating the TA Lumen Tube by the BLF community, I have a feeling that many manufacturers, especially the smaller ones, might be using integrating spheres that are not calibrated correctly without knowing it themselves. Prior to the calibrated TA Tube, most DIY measurements by BLF users are also miscalibrated higher than they should and this includes TA’s own measurements from before, which were about 32% higher than his current calibration. Even Djozz’s lumen measurements are, correct me if I’m wrong, still kept about 12% higher to be consistent with his previous measurements. The price of a certified integrating sphere is the price of a couple thousand cheap flashlights so most bargain manufacturers cannot afford one.
I don’t know if Imalent has a certified integrating sphere or properly calibrated measurement device. I read a few user reviews that measure the DX80 to be about 30k to 32k lumens, which is pretty good considering typical variations within the same model but the DN70 measured significantly less than the rated 3800 lumens. However, I no longer fully trust these user measurements unless it’s measured by Maukka or a calibrated TA Lumen Tube that fits the light head.
If you already measured several flashlights with TA’s lumen tube, you can measure again a couple of those flashlights and the MS12 with a ceiling bounce in a small room with white walls. It won’t be super accurate but will probably be more relevant than with a lot of light escaping from TA’s lumen Tube.
Rough estimate #1:
Output MS12 ≈ ((5.1^2)/(3.5)^2) * 25000 = 53k lumen.
So ironically it's spot on with Imalent's specs. Of course this is a rough calculation, and surely there are reasons why it's insufficiently accurate. But it's a method.
I could just as easily say lumen = candela * steradian
So we can calculate the steradian as Ω=2π(1-cos(θ/2) and candela with the formula candela = lx * (distance in meters)2
Ω=2π(1-cos(θ/2) where my θ = 38.83 , ≅.3593 steradian
candela = lx * (distance in meters)2 which is as follows candela = 4100 * (6.096)2 ≅ 152360 cd
lumen = 152360 * .3593 ≅ 54742 lm
How did you get your theta you say? Some measurements and the law of sines.
But all of these formulas make many assumptions and I have very little confidence in the final result. I did this math a few days ago, but you can't just make these assumptions and claim the reading is valid. Now I am sure everyone is going to say "Mark said the MS12 flashlight is rated at 54742 lm!" :FACEPALM:
Throwers always read higher on ceiling bounce tests so I had to calibrate the ceiling bounce app with a beam that was close in area to the MS12’s.
First I ceiling bounced it against a DX80 which people got 30k for and the MS12 measured 43k. The MS12 has wider spill than the DX80 though so I ceiling bounced the MS12 against a roughly 15000 lumen Acebeam X45 which has a very similar beam profile and the MS12 measured 53,000 exactly!
I then did a 10 minute runtime test from Turbo and abandoned it due to excessive temps. I couldn’t hold the light at around 6 mins.
The button area was 56c and head 86c, the fan didn’t seem to have much effect on external temps.
Wow! 86c is extremely high, I can’t recall what was the temperature when someone did extreme test on Haikelite MTO9R. At this temperature, the fan has to rotate in such hot air environment, the fan might contribute more heat that trapped in there too. I am thinking of convection oven theory.
I’m guessing that the MS12 did not kick down enough or fast enough like it should. If it did go down to 15,000 lumen, it might have been sucking in hot air and circulating it instead of getting fresh air.
I wonder why it got so hot?
I think this is the problem of the fan cooled lights.So,I guess that Acebeam understood this and so,put the fan in the handle so as to suck, and then pump fresh air.
There’s a wide variety of different actively cooled light designs. Some of which work extremely well.
Just done another 10 minute run this morning: head 65c, button area 45c - HUGE DIFFERENCE!!!
Handle was very comfortable to hold with the button being a little hot to press. Not sure why the extreme differences, fan kicked in at 3 mins as well, not 2 mins like yesterday.
Bizarre!
Turbo started stepping down from 5.30mins, it took 30 seconds to get to 15,000. Reactivating Turbo at 9 minutes was pointless it stepped down sharply.
The fan does seem to go at different speeds occasionally so might be something in that.
Both tests are with batteries freshly charged?
If second test has less juice in batteries, it might not have same output power.
Dethroned
Probably 4.20v for 1st and around 4.10v for second, I’ll test again at 4.20v later
???
I think he refers to the x70 which will have more lumens and be the new king?
Oh. So if Acebeam decides to not release the X70, then it’s still the king or not? Who knows?
I will wait until the X70 is released and measured against the MS12 before I say which is king. Right now MS12 is king.
Specs are out on X70, looks like it will not run more then 15k continous, 25k at 8min and 60k at 55 seconds!
I think Imalent didn’t invest in real thermal regulation even for this flagship product.
Below is the thermal vs lumen percentage graph of my Zebralight S6330 that I did years ago. It regulate the output so that temperature doesn’t cross a predefined temperature, in this case around 60 degree celcius for external temperature. It actually increased the output when it see temperature dropped enough. But I have no way to know the internal temperature that definitely rise much faster than external temperature, that is why we see the output dropped soon after 1 minute.
Of course they didn’t.
No way you can compare these two brands.
Zebralight uses a very advanced thermal regulation that can decrease as well as increase the output. No way Imalent is using something that advanced.
Anyway, it seems it was a fluke. On the second try it cooled down properly. So Imalent probably has some glitchy software controlling the temps.