Hi,
Which one to choose?
or
I need maximum lumen without step down at room temperature.
Probably 50% mode is OK for this requirement.
Question is: Which light will give more lumen?
I found review of S11 GT FC40 and I can say that FC40 is total crap as lumens. So, I will pass.
Hope Convoy launch soon M21B with XHP70.2.
The FC40 is very high CRI with good tint, the XHP70.2 isn’t high CRI and can look like a fried egg. Due to the huge difference in CRI, the FC40 has less lumens/watt.
I really like my new M21b with 5000K FC40. I also order M21E and the spot is defective I think. There I’d yellow tint in spot. Also I have M21C with 4000K FC40. 5000K have more lumens maybe 150 more compared to 4000k version. If you want M21B with XHP70.2 why not made your own. There is host and driver and MPCB for that.
XHP70.2 have best lumens per wat.
I ordered M21B XHP50.2.
It is 2300 lumen at 100% and probaly can hold 50%.
I want XHP70.2 because it has 3000 lumen at 100% and will hold 50% - 1500 lumen.
It is 1.5 more than XHP50.2
I am intersted at 50, because drivers has regulation at lower battery voltage levels than 100 mode.
Anyway. Simon will add М21B with XHP70.2
The M21E comes with that emitter?
It’s a steal, and it’s rechargeable!
M21E
Convoy’s 5000K XHP70.2 is P4 3A bin. So if you want maximum lumens, then that’s a good one with possibly little rosy tint.
4000K is N4 5A. Not so efficient, but tint is probably good.
I preffer M21A 12 group UI and mechanical switch.
Simon just release XHP70.2 version of M21B
https://www.aliexpress.com/item/1005003357857496.html?spm=a2g0o.store_pc_home.productList_644232540.subject_0
I have a question 
Experimental set-up:
- M21B GT FC 40
- M21B XHP 50.2
- M21B XHP 70.2
- all three flashlights are powered with 5A
When each flashlight runs on turbo mode (5A), will the GT FC 40 heat up faster and reach a higher maximum temperature compared to the XHP 50.2/70.2? And if so, how much temperature difference will it make?
Will the GT FC 40’s lumens output be the lowest because it’s not as efficient compared to the XHP LEDs?
I just found two different reviews. One is about the S11 GT FC 40, the other one is about the M21B SST40. It states the following data about measured lumens and tailcap amps: S11 GT FC 40 (716 lumens/2.37A), M21B SST40 (738 lumens/1.52A). So, the GT FC 40 will consume horribly more amperes to reach a comparable lumens output. At the same time, the GT FC 40 will produce a little bit more heat than the SST40.
Thank you!
If the GT-FC40 and XHP70.2 are both 12V and running at 2.5A (I think they use a 2.5A input driver) then the XHP70.2 will produce more lumens (and in theory heat up slower). However, the GT-FC40 has considerably better CRI. So your choice is between lots of high CRI lumens, or approx. 40% more low CRI lumens.
question465 you can’t compare LEDs by current only, you must use power not current. Right measurements are lumens per watt not lumens per amper. There is great little russian program where you can compare different leds but it is only in russian language.
http://forum.fonarevka.ru/showthread.php?t=2702
Online version have English interface but it is not very good compared to standalone version.
30W for 5000K GT-FC40 produces~2600 lumens, if I take values from Djozz’s test. M4 binned 5000K XHP70.2 90cri will produce about 4200 lumens with 30W, if I take values from similarily binned 80cri version led from Texas_Ace’s test. So with quick calculation XHP70.2 produces 61% more lumens with 30 watts even with 90cri version.
Edit: To simplify: with same amount of heat XHP70.2 produces 61% more light.
Since XHP70.2 is crap LED and the other flashlight is high CRI there is nothing to deliberate.
Mike
To reply to the original poster: FC40 for better light quality, XHP70.2 in 5000K if you just need lots of it.
I have the Convoy M3-C xhp70.2 5000k. It may not be high CRI but it is pleasing to my eye. A bunch of lumens with little heat also. Very little step down from turbo in warm weather and in the winter I see no step down.