chillinn
Flashlight Enthusiast
According to one of my favorite and most consulted posts (by rikvee, last seen Feb. 2016), the MN21 (for M6 KT4) draws 4.9A on 6x CR123A for 20 minutes. Everywhere I have looked says the lamp is 500Lm.
What I was wondering, first of all, is if one 500Lm incan the same as the next? Or is this lamp super intense for 500Lm (whatever that means)? The curious thing about it is that it is 4.9A, which I would expect to mean it puts out a lot more than 500Lm, maybe 3-5 times more, and Surefire cleverly underestimates while other manufacturers lie about lumens, or maybe 500Lm is the average lumens across 6x CR123A discharge profile.
rikvee's post includes a lot of lamps intended for CR123A that also run on similar voltages of Li-ion. Generally,
I have learned here to assume that CR123A drop to 2.5V under load, and extrapolated that figure can be matched to Li-ion nominal voltage (3.6V/3.7V) to match voltages between number of CR123A and number of Li-ion. But CR123A@2.5V under load is probably no longer true at close to 5A, leading me to guess that the MN21 may be nominally 18V but truly 12V, which should run at close to 500Lm on 3x IMR, or 11.1V nominally, though 3x IMR resting voltage adds up 12.6V. But maybe it will not immediately flash on 4x IMR, 14.8V nominal, 16.8V resting, though these lamps seem to be pretty rare, so it would be very good to know beforehand if ever one finds its way to me.
Lastly, B&H kindly leaves up old product pages, including the MN21, but has a second product page for MN21CS. What is that? What's the difference? Specs look the same as MN21.
FWIW, my interest has turned to lamp assemblies since two of Tad's last three G4 sockets sold about a week ago, and I had fully intended to purchase all three in about 3 days. I contacted Tad, and he was kind enough to pull the last G4 socket for me so I don't miss it. Ultimately, I want a total of four lights with a KT4 head, though this will take some time on my budget. Then I'd really like to hook up with some caving photographers, though I'm not going very deep into any cave. Shallow caving photographers, then, might be interested in me and my lights.
What I was wondering, first of all, is if one 500Lm incan the same as the next? Or is this lamp super intense for 500Lm (whatever that means)? The curious thing about it is that it is 4.9A, which I would expect to mean it puts out a lot more than 500Lm, maybe 3-5 times more, and Surefire cleverly underestimates while other manufacturers lie about lumens, or maybe 500Lm is the average lumens across 6x CR123A discharge profile.
rikvee's post includes a lot of lamps intended for CR123A that also run on similar voltages of Li-ion. Generally,
- 2x CR123A ~ 1x Li-ion
- 3x CR123A ~ 2x Li-ion
- 4x CR123A ~ 2x Li-ion
I have learned here to assume that CR123A drop to 2.5V under load, and extrapolated that figure can be matched to Li-ion nominal voltage (3.6V/3.7V) to match voltages between number of CR123A and number of Li-ion. But CR123A@2.5V under load is probably no longer true at close to 5A, leading me to guess that the MN21 may be nominally 18V but truly 12V, which should run at close to 500Lm on 3x IMR, or 11.1V nominally, though 3x IMR resting voltage adds up 12.6V. But maybe it will not immediately flash on 4x IMR, 14.8V nominal, 16.8V resting, though these lamps seem to be pretty rare, so it would be very good to know beforehand if ever one finds its way to me.
Lastly, B&H kindly leaves up old product pages, including the MN21, but has a second product page for MN21CS. What is that? What's the difference? Specs look the same as MN21.
FWIW, my interest has turned to lamp assemblies since two of Tad's last three G4 sockets sold about a week ago, and I had fully intended to purchase all three in about 3 days. I contacted Tad, and he was kind enough to pull the last G4 socket for me so I don't miss it. Ultimately, I want a total of four lights with a KT4 head, though this will take some time on my budget. Then I'd really like to hook up with some caving photographers, though I'm not going very deep into any cave. Shallow caving photographers, then, might be interested in me and my lights.
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