first some day shots... to show the difference between the Ultrafire M51 and Acebeam K40M
The head of the K40M is much larger. And because of the Smooth reflector throws quite a bit farther than the M51.
The Ultrafire M51 measured 31175cd While the K40M measured about double the M51 at +/-60000cd
The K40M has double the throw, and about 1000 lumens more output.
The M51 will give you 95 minutes of runtime in Max.
The K40M will give you 65 minutes of runtime in Max.
Throw comparison/Beamshots comparison:
Mouse OUT K40M,,, mouse OVER M51
and throw
The M51 is a little "warmer" than the K40M..
Acebeam K40M
Ultrafire M51
Modes
6+strobe
4+ strobe
UI
Simple with mag control
Not very good
Stainless steel bezel
No
Yes
Holster
Yes, (soft)
Yes, (hard)
1 handed operation
Not really
Yes
weight
642grams
642grams
Balance
Front heavy
Well balanced
Size
X
O
Throw
62500
31750
Output
+/- 3000
+/- 2000
Runtime max output
65minutes
97minutes
only in max modes on both lights
Grip
X
O
If you just want a great light with an MT-G2, and don`t care about stainless bezel, more pocketable etc... go for the K40M.
But the M51 has some advantages as well...
Very easy to operate with 1 hand, and more pocketable.
Runtime in MAX output is longer, but has less output.
But you would always be able to get at least 1.5 hours of runtime on the M51.
Although the weight is the same, its balances better on the M51, as well as the knurling.
So they are different lights..
I still think the K40M will give you more value for the money.. but the M51 has some characteristics that could be Better for Some people... so don`t rule out the M51... especially if you can find one for a good price below the $100 mark.
You say there is no glue on any of the main parts and that they can be unscrewed. Wasn't the driver compartment screws sealed (and probably used loctite on)? They were on my light.
You say runtime on Ultrafire M51 is an advantage. But, you could just set the K40M on level 5 and have roughly the same output and runtime? I dont know how the lowest mode is or efficiency on low on the M51 is (did your review cover that?). My guess is that K40M does have the advantage when it comes to max runtime (on lowest level). If that is the case, im not sure how the M51 have any real advantages in terms of runtime.
Thanks for the review ChibiM! Very valuable information. A few questions and comments:
Other people might disagree, but those small pictures showing the diminishing output aren’t useful to me. The differences are too small for me to see. The graphs are great though.
In the sentences I’ve quoted from your original post above, there seems to be some contradiction. Could you clarify what you mean please?
About the brightness indicator, my guess is that the “ramp” image isn’t supposed to cover modes 1-6. I think they just used a small ramp image that you could see at a glance. Similar to an On/Off switch that’s labelled “0/I” at one end, but isn’t labelled at the other end.
Excellent review! Very thorough!
But for one thing, at the very beginning, it says working voltage ~4V. Isn’t the MT-G2 a 6V emitter? But of course we know that it is. Looks like a factory mistake.
Nice pics, very detailed work.
Thanks!
Yep, you are right about the driver.... But I was more referring to the "main parts, as body, bezel, and tailcap.
The driver belongs in the "special inner parts" ;)
I will edit the text, and make that clear, that the inner parts are glued!
Tried even to get the glue out, and remove the driver.. but without success.
Again you are right..
at this point, I was referring in the comparison the runtime in MAX mode.. regardless output..
Kind of like this: The Minimum runtime on the M51 is .......minutes.. vs .....minutes on the K40M.
Again, will make that point more clear in the review!
K40M will have longer runtime in Level 4, than M51 in Max.
Thanks for the questions as well.
Could you please explain where the contradictions are?
I`ll try to explain (not 1 by 1) what I mean, maybe that would clear it up.
The UI is very easy to understand! and can be used by anybody! (as long as someone has a working memory ;) )
It is very easy to change outputs, and therefore its a big plus!!!
Compare it to lets say; Eagletac lights, or lights with hidden modes.. people could have trouble just remembering how to change modes.... same like with the M51, which UI isn`t really the best.
The light can be operated by only 1 hand, but I assume that this light is designed for that.
So I mentioned that it is really hard to operate with only 1 hand, and in comparison to the M51 that could be a CON.
But at the same time very reliable and easy to operate with 2 hands.
So when I refer to the good sides, I imply the use of 2 hands...
the rest (negative) is referring to a 1-hand operation.
Yes, I didn`t know how to "name that little brightness indicator".
about the pictures:
Just showing the steps of output difference can still be seen in the smaller pics.. and in the second post I have comparison pictures with the M51, which are bigger.. on purpose, as I think its more relevant then.
I just didnt think I wanted to take so much space in the review with just beamshots of the 6 levels. I hoped the output difference would be understood with looking at the table.
yes, the runtime has been mentioned by Racer86 as well, and I explained it in my reply.. its the longer runtime in its max mode.. (although with lower output)
Yes, I measured it and its DTP..
I put 1 probe besides the MT-G2 where it has a little blank space of copper, and the other one on one of the screws, and it had continuity....