One thing about the big bad wolf TIR is it’s clear like crystal, very pretty, but it shows dirt or scratch/imperfection clearly. Annoying especially for the OCD type among us. I guess the dirt specs could be clean but bottom line is be careful if you are going to take the optic out. I am leaving mine alone, for now.
Opening our beloved Convoys has always been a fun adventure for me. Like a box of chocolate . You don’t really know what you’ll find, the gasket or lack thereof, the thermal paste or lack thereof, whether the tight TIR has decapitated that treasured and no longer made 519a 4500k’s dome, etc. But for this M21K I will skip the fun exploration.
Thanks to @thefreeman we have some info on M21K driver. And thanks to @macomako 's TASI discovery, here is runtime with the TASI meter. The battery used was EVE 50PL. Test is run at Turbo-1, aka Level 4, the highest level of the stepped ramping levels.
Looks regulated c/w thefreeman’s info. Active cooling means I have a fan blowing at the light, ~2 feet away.
Oh that’s just Photoshop. I opened then saved PDF file as jpeg (using Windows “Snipe”) and erased unwanted text and added my own text to the jpeg file using Photoshop.
Question: seems there is no way to NOT display that max level on the PDF file? Only way is to graph excel data?
I don’t have a calibrated setup (integrating sphere + light meter) so the lux results I’m getting from my TASI cannot be considered the total lumen flux coming out of the flashlight (hence % / relative value on my graph instead)
I’m totally okay with that because that was my goal
Summary of M21K measurements. I included a couple other lights, for no reasons other than they are 7070 footprint, 30 buck walk lights with “interesting” LEDs that I recently bought. There is no “winner” because there are many factors involved. For example LW55 is brightest and throws furthest, but it’s a harsh white beam whereas LHP73B 4000k is a warm beam with outstanding tint and shows colors of plants & flowers etc. beautifully.
Convoy M21K with LHP73B 4000k CCT 4000k, Duv 0.0000, CRI 70 Output: 5900 lm Momentary Turbo with EVE 50PL ANSI Throw @ Turbo: 163 Kcd, 810 m with EVE 50PL
Nightwatch LW55 with Mystery LED N7-170HPSummary HERE CCT 6400k, Duv 0.0010, CRI 70 Output:8180 lm with EVE 40PL ANSI Throw:189 kcd, 870 m with EVE 40PL
IMHO, the emphasis on LHP73B 4000k is not just the impressive 6000 lm output, but its warm CCT and non greenish tint (not a trace). Indeed the warm beam with beautiful tint shows off especially when looking at the colors of nature, plants, flowers, etc.
The TIR beam has a large hotspot, with a faint spill. I love the large hotspot because it makes far field of vision satisfying large; no pencil beam here. Faint spill means peripheral illumination in near field ~20 ft or less (eg the area in front of your feet) is not as bright as LW55’s OP reflector.
Unlike for example my Firefly X1L with frosted TIR and a smooth beam, this narrow angle clear TIR to squeeze throw has some IMHO mild ring artifacts in corona and wind spinner shadows in the spill. This is bothersome if you are an OCD white-waller (you know who you are ;=)), but not a factor in actual use, for me.
I got the 5000K version. I am a bit underwhelmed by it. I will have to take some pics, the beam has several very noticeable rings. It is not anywhere close to being the nice smooth beam that you capture in the pic above.. The light is OK, maybe all of the anticipation and hype around it led my expectations to be too high.
These are just initial observations. I haven’t taken any measurements or checked run time. I did run it in the momentary turbo mode for 30 seconds using the 50XG cell. Nothing burned up and I can’t see any problems with the LED. So there is that…
Your preception is correct. Human vision (eye + brain processing + pupil, continually adjusting) has vastly greater dynamice range, roughly 20 stops vs 10 stops, than a single snapshot from a camera (one exposure setting, one moment in time). That’s why our perception of the beamshot for shadows and highlights is better than a picture. As hard-core into photography as I am, I always describe and trust first what I see with my eyes, and use photography to supplement/confirm/etc., not the other way around.
Thrower beam could be nasty, why I frequently make a point of warning about white walling throwers say on a ceiling 2-3 meters away. Personally I use my 10 meter “rule” (the length of my living room + family room lol). If any beam artifact still bothers me at that distance, then that light is not for me (Wurkkos TS30S Pro comes close). Both LW55 and M21K pass for me, but each of us has different tolerance, vision, etc., so definitely YMMV.
Beam shot comparison of 2 excellent LEDs with very similar beam colors in actual use. But LHP73B is going to be tough competition for XHP when it comes to output.
My XHP70.3 HI R70 4000k is a lottery winner: center is ever so slightly rosy with Duv -0.0010, the spill-corona border area has higher Duv 0.0030. The periphery area of XHP looks very slightly greenish only when you simultaneously white-wall compare with a rosy LED. OTOH, I have no criticism of LHP70B’s tint, the 4000k version; it’s beautiful. I suspect Simon concentrates on making this parameter perfect.
There is a huge gap in output. Simply put LHP73B doubles up XHP70.3. The highest step of LHP73B at ~3000 lm is as bright as Turbo of XHP70.3. However I still love my XHP. Why? I only need 1000 lm for a majority of the walk. OTOH yes the brightness difference is huge, when you need it.
Were you to ask if I am REALLY impressed with the 6000 lm output of the LHP73B, the answer is actually NO. Impressed, yes, but really impressed? NO lol. I have 2 Nightwatchs (the LW55 below) and the Mateminco D3 that are brighter.
What does make this LED unique, however, is this 6000 lm is paired with warm CCT and fantastic tint. IMHO, this is the number 1 item on the list of PRO vs CON for this LED.
The only other LED that has similar CCT and great tint in my small collection, is the XHP70.3 HI R70 4000k below. I love it, but its output is 3000 lm, half of LHP73B.
M21K is a serious thrower, borderline SUPER-thrower class (my made up rule of 1km throw). In my (small) collection of lights, only two LEDs outperform LHP73B in similar host size, and they are both dedicated throw specialists, the Firefly 991MX, and of course, that famous SBT90.2. (PS The third one is the mystery LED in Nightwatch LW55.)
But… both of those LEDs have a nasty green tint (to my eyes, YMMV), and mystery LED is harsh white 6500k. So… LHP73B’s brightness and throw performance is already top-notch, but made even more special when taken in context of its warm CCT and beautiful tint. This is what makes this LED unique. IMHO.
The M21J, which uses the same optic and the SFT90, only achieves 794m of throw per ZeroAir, yet your measurement of the floodier LHP73B indicates 810m. Something isn’t quite right.
Some back-of-the-envelope calculations suggest that one/both of the following may have occurred: (1) ZeroAir underestimated throw on the SFT90, likely due to insufficient measurement distance, and (2) you overestimated throw on the LHP73B. The former may be more likely, since your measurements for other lights seem reasonable.
Sure - IMHO 800 m is borderline super-thrower. Very happy I opted for M21K, however absolutely nothing wrong with pairing this LED with a different optic to get the preferred beam profile. OP reflector of M21E should yield a beam with more even brightness spread, less jarring/super-bright hotspot. It should be better for shorter distance.
Another advantage of M21E: Even though M21K passes my own 10 meter rule (for throwers, look at beam at least 10m away to see whether artifacts are acceptable to you), if artifact free beam is desirable, M21E is also the host I would recommend. The penalty will likely be shorter throw. Lastly, the one remaining unknown is heat dissipation of smaller M21E’s head vs M21K’s.
Either optic, you will benefit from the defining features of this high power LED, warm CCT and beautiful tint. I suspect this was what Simon aimed for during its design. In this day and age, highis lumen count alone is not that special anymore.
Brightness in real world use outdoor is very impressive, among the highest sustained output in my small light collection. The result below is from a 20 minute walk, last ~10 in high mode, in California winter weather 15 degree C @ 6 am. Flashlight temp measured with IR gun about 1" from On/Off button.
Start: 3200 lm, 22° C (Highest stepped ramp level)
End: 3200 lm, 48° C (Subjectively very warm, borderline hot, but holdable.)
I love brightness, especially sustained at this fantastic level . This alone makes me want to buy a second M21K with 5000k CCT. It is consistent with excellent M21K runtime with active cooling below.
But… neither test is hot enough to “challenge” M21K. To really investigate M21K thermal management, I will need to do indoor runtime, without active cooling. IME inndoor vs outdoor could result in big difference.
This is the TASI light meter and grapher, my amateur “equipment” (ok yes it’s a shoebox ) for measuring runtime, eg the graph above.
There is very little heat transfer as test is indoor, there is no air movement, and during the test part of the flashlight’s head is inside that box that would be closed shut. The difference between the runtime test and actual use outdoor us is obviously significant, but this somewhat worst case scenario is “best I can do”.
TASI gives “relative” brightness data for the graph, like 100% at start, 50% after 5 minutes, etc. The actual/true brightness, that 3200 lm in the graph, requires a separate measurment using my Texas Ace lumen tube.
Just pointing out why the outputs vary so much between these 3 LEDs. The difference are not just from the LEDs, the drivers themselves are significantly different from each other:
1. M21E w/ XHP70.3 is lowest, 3100 lm: The driver for this LED has max Turbo at 6v x 5a = 30 watts, providing half the energy of LHP73B with Buck driver at 3v x 20a = 60 watts. 2. Nightwatch LW55 8200 lm vs Convoy M21K 6000 lm: LW55 's Turbo is likely FET direct drive, versus Buck driver of M21K, where Turbo is limited to 20a.
M21E when paired with LHP73B will use the same 60 watt driver as M21K, so I would expect the output to be in that 6000 lm range also.
. You don’t really know what you’ll find, the gasket or lack thereof, the thermal paste or lack thereof, whether the tight TIR has decapitated that treasured and no longer made 519a 4500k’s dome, etc. But for this M21K I will skip the fun exploration.
. This alone makes me want to buy a second M21K with 5000k CCT. It is consistent with excellent M21K runtime with active cooling below.
) for measuring runtime, eg the graph above.
