Jetbeam Jet-u and Fenix L0D-CE 1AAA shootout: RUNTIMES, BEAMSHOTS, and TEMPERATURES

selfbuilt

selfbuilt

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Jetbeam Jet-µ and Fenix L0D-CE 1AAA shootout: RUNTIMES, BEAMSHOTS, and TEMPERATURES

The contenders:

Fenix L0D-CE on left (bought at the Fenix-store.com several months ago, and my main EDC ever since), Jetbeam Jet-µ on the right (just received by air mail directly from JetBeam)
1AAA.jpg


Method:

Home-made lightbox a la Quickbeam's FR.com method. My relative overall output numbers are typically similar to his, although generally a little lower. You can directly compare the runtime graphs - i.e. an output value of "10" in one graph is the same as "10" in another.

Beamshots:

The relative output can be a bit misleading, given how the Jet-µ is almost all flood and the L0D-CE is a traditional spot beam with spill. Believe it or not, my lightbox reports the Jet-µ is brighter in most modes (see runtimes below). Relative output differences were confirmed by the “ceiling bounce” test in a small window-less room.

All beamshots below done on L92 Energizer e2 lithium batteries, at same exposure settings: 1/10sec exposure, F-stop 2.8, daylight white balance. Lights are about ~0.5M from the wall, to better show the spillbeams.

Low mode: L0D-CE on left, Jet-µ on right
Jetu-Lo.jpg


Primary (medium) mode: L0D-CE on left, Jet-µ on right
Jetu-Prim.jpg


Hi mode: L0D-CE on left, Jet-µ on right
Jetu-Hi.jpg


Runtimes:

All runtimes done in my lightbox under a cooling fan, with the identified batteries listed below.

1AAAhi.gif


1AAAprim.gif


1AAAlo.gif


For Li-ion, I used a pair of AW 320mAh unprotected 10440s, sold in the Dealer’s forum with a Nano charger.

1AAAprim10440.gif


For the 10440 Lo mode run, I very briefly stopped the run at 1 hour intervals to verify the voltage on the 10440s (both 4.17V to start), and then continued the runtimes. Note that it's dangerous to run these down as far as I did (i.e. 75% initial output). In practice, I'd never let a light go below ~3.65V, because it's a rapid voltage "ski-slope" down from there.

1AAAlo10440.gif


Notes:
PWM: The L0D-CE uses 100 Hz in primary and low, the Jet-µ uses 314 Hz in primary and low. The L0D-CE strobes at 8.3 Hz, the Jet-µ at 7.6 Hz.
Mode Sequence: L0D-CE sequence is primary-low-hi-strobe-sos. The Jet-µ is primary-low-hi-strobe-standby. The Jet-µ also has a memory feature that memorizes the last mode used if you leave it in that mode for more than 1-2secs (a quick flash shows you memory is activated). When you turn the light back on, it will return to this last mode use (when the feature is working properly – see below for a discussion).
Li-ion 10440 compatibility: Although both lights can take 10440, running in Hi mode is not recommend for prolonged periods on either. In fact, the Jet-µ’s SSC emitter can’t last more than a few secs without turning bright blue (a sign of over-heating).

Here’s a few beamshots showing the Jet-µ on Hi on 10440 on the right, against my Surefire L2 on Hi on the left (all beamshots at 1/100sec exposure, F2.8, daylight white balance):

5 secs: L2 on left, Jet-µ on right
Jetu10440-5sec.jpg


10secs: L2 on left, Jet-µ on right
Jetu10440-10sec.jpg


15secs: L2 on left, Jet-µ on right
Jetu10440-15sec.jpg


In real life, it doesn’t seem quite as blue as the images suggest, but you can tell it’s pretty bad!

I’ve done some temperature readings of the exterior surface of the head of the L0D-CE and Jet-u, both near the lens using a flexible temp probe taped down. No external cooling is applied for this test. Readings taken at 5sec intervals:

1AAAtemp.gif


Frankly, I really risked destroying my Jet-µ emitter in the test above – WAY too blue after 45secs! And too hot to hold - very unpleasant unscrewing the head by hand above >50 C, let me tell you.

Key observations:

  • L0D-CE is a traditional spot/spill beam, whereas the Jet-µ is almost all flood. This gives the mistaken subjective impression the L0D-CE is brighter, when it fact my lightbox and “ceiling bounce” tests all confirm the Jet-µ is brighter in most modes on most batteries.
  • Overall build quality is generally good on both, although the threads on the Jet-µ are very small and narrow, being on the interior surface of the battery tubes (i.e. just like the JB C-LE). Along with the foam spacer to stop battery rattle, this can make it harder to reliably switch modes on the Jet-µ (especially single-handed)
  • The sequence and memory mode features of the Jet-µ only work if you keep the screw threads and all contacts *scrupulously* clean. A lot gunk quickly builds up in the threads of the Jet-µ, causing out-of-sequence errors, missed modes, forgotten memory, etc.
  • The L0D-CE seems to outperform in terms of runtime on all tests, but Jet-µ runtimes are still acceptable, especially considering its typically higher output.
  • 10440 batteries cannot safely be used on Hi in the Jet-µ without risking serious damage to emitter very quickly. Of course, 10440 on Hi is not recommended on the L0D-CE either, as thermal runaway could occur without you even realizing it (i.e. no tint-shift occurs on the Cree). The Jet-µ also quickly becomes too hot to hold, much faster than the L0D-CE does in this mode.
  • I didn’t see any tint-shifting on 10440 in primary (medium) mode on the Jet-µ during runtime tests, but those tests were done under a cooling fan
  • 10440 on Lo is the one time the Jet-µ exceeded the runtime of the L0D-CE for an equivalent output
Jet-µ Conclusions

Pros :
  • One of the floodiest beams I’ve seen (good for a keychain EDC, in my opinion)
  • Uses higher PWM freq, so less “flicker” noticeable
  • Standby (i.e. beacon) likely more useful than SOS
  • Memory mode good idea if you want to insure light comes on in certain state, but may need to cycle through strobe/standby to get back to earlier modes
  • Blue-tint shifting of SSC good indicator if over-heating occurs
  • Ability to run 10440, and more efficiently in Lo mode than the L0D-CE. But Hi on 10440 does not seem feasible for any amount of time on the Jet-µ (of course, I personally don't recommend Hi mode on the L0D-CE either)
Cons:
  • Floody beam gives subjective impression of being dimmer than it actually is
  • Screw threads have relatively poor feel and greater tension, making it difficult to reliably shift modes.
  • Threads get dirty quickly, leading to out-of-sequence errors and forgotten memory mode (similar problem to the new v1.2 C-LE). Maintenance level is thus higher than the L0D-CE
  • Runtime lower than L0D-CE in almost all tests of various modes on various batteries - although with typically higher output of the Jet-µ
  • Poor heatsinking compared to L0D-CE, as evidenced in 10440 Hi mode tests

As always, your call what suits you best. Cheers!
:twothumbs
 
Last edited:
mchlwise

mchlwise

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EXCELLENT comparison and review. :twothumbs

I've been very interested in this comparison, since I was between these two lights.

I went with a JetBeam, which I should be getting any day now, and might be sorry. :sigh:

I really like the style of the JetBeam, but the Fenix seems to out-perform it in every respect (though the Jet puts out more actual light, the Fenix will still "feel" brighter).
 
T

Tronic

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Thanks for this great comparison! :twothumbs
 
A

aceo07

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Thanks for the detailed review.

I wish the runtimes were much better, especially for low.
 
Last edited:
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nerdgineer

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Another excellent review, selfbuilt. You are making yourself the new biblical reference standard for flashlight reviews....:clap:.

BTW, you have once again confirmed my opinion that Fenix remains the current champion for battery efficiency in flashlight design.
 
J

jsr

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Wowzers that's an amazing review. Has so much great detailed info and objective test results. The only thing that would make it better is more pics...sorry, flashlight p*rn.:)

I almost pulled the trigger on a Jet-u...it looks soooo nice, but held off due to the previous MKII and MKIIx Jetbeam releases reporting so many issues. Glad I did. I do like the increased output, but the contact issues make it a no go for me. I like to use my lights and not have to worry how clean the threads are. All my lights work even with dirty threads...sure, they might not be optimally bright, but if I need light, or need to switch modes, I know it will work.
 
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THE_dAY

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:thumbsup:just the reveiw i and many others were looking for!

thanks selfbuilt!
 
selfbuilt

selfbuilt

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Thanks for all the positive comments everyone.

I too am a little disappointed with the Jet-u runtime on low. Just double-checked Chevrofreak's excellent curves for the L0D-CE, and it seems mine is star performer - my L0D-CE lasted almost an hour and half longer than his did on alkaline.

I'm going to try the Duracell 1000mAh NiMH on low on both lights, and will update the graphs above when it's done (likely sometime tomorrow).

As for flashlight p*rn, x2x3x2 has always has great detailed disassembly pics on his review site, and ernsanada always does excellent outdoor shots. I figure I can't compete there, so I thought I'd save my bandwidth for beamshots and graph. ;)
 
ernsanada

ernsanada

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What distance did you shoot your beam shots?
 
selfbuilt

selfbuilt

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What distance did you shoot your beam shots?
I didn't measure exactly, but it was about half a meter (~0.5M). Roughly the same as the beamshots in my multi-level 1AA review.
 
regulator

regulator

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Nice review and great info Selfbuilt. Do you think you could do a runtime plot running low mode with a lithium ion cell. It is supposed to provide more light than medium mode using a NiMh but substantially longer runtime - 3.5 hours.

Thanks.
 
L

lumenal

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Excellent comparisons selfbuilt. Thanks for the time and effort. :twothumbs

I've been on the fence regarding these 2 lights - it seems the Fenix Lod Ce is the one for me.
 
selfbuilt

selfbuilt

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Nice review and great info Selfbuilt. Do you think you could do a runtime plot running low mode with a lithium ion cell. It is supposed to provide more light than medium mode using a NiMh but substantially longer runtime - 3.5 hours.
I'm currently doing NiMH run tests, but may try it tomorrow. I'm wary of low mode 10440 runs, because you have to watch it like a hawk to make sure you don't run down your batts. I may stop the runs at intervals to test voltage, to be on safe side. I'll keep you posted ...
 
GhostReaction

GhostReaction

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Excellent comparison review. :twothumbs:

It makes my option clear on which light to choose.

Hope you would do more great reviews
 
G

Grumpy

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My two Jet-u lights do not remember the last setting unless I leave them turned off for 15 seconds before turning back on. Anyone else have this same issue?

As I understand it if I leave the light on more than one second and it blinks I should be able to turn it off and it should come back on at the previous level.

It does not unless I leave it off for several seconds before turning it back on.

I think that this is a defect. Anyone else have this same problem?
 
selfbuilt

selfbuilt

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Just updated the low graph to include NiMH runtimes. The Jet-u clearly does better on NiMH than it did on alkaline. Interesting that my L0D-CE has exactly the same runtime to 50% on alkaline with NiMH, with only a slight bump in output (usually see more of a difference between battery types on most lights). The Fenix clearly seems to have a very well optimized circuit for running on low mode. 10440 low mode runs are currently underway.

FYI, I'm also working on a review of some of the popular single-stage 1AA cree/SSC lights from DX/Kai, as compared to earlier models I've moded to cree/SSC (e.g. Elly, Vippa, etc.). Should have at least the preliminary review up by the weekend, assuming the last of the lights arrive as expected.

Oh, and I'm about to update my multi-level 1AA cree/SSC light review with the new v1.2 C-LE runtimes:
Rexlight, DX X.1 & X.V, Jetbeam MkIIX & CLE, Fenix L1DCE review: RUNTIMES + BEAMSHOTS

That review will continue to be updated as new lights come in (especially the LM-301 which has just shipped :)).
 
gunga

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You rock selfbuilt! THese reviews are so helpful!

I'm also extra proud your a Canadian!

No more of this CONUS stuff...

:D
 
selfbuilt

selfbuilt

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Thanks for all kudos - it's nice to know the results are appreciated! :)

Just added the Lo mode runtime on 10440, and the Jet-u finally pulled ahead of the L0D-CE. Nearly 2.5 hours to drop-off on the Jet-u vs 2 hours on the LOD-CE, for exactly the same output.

Too bad about the Jet-u Hi mode results on 10440, but honestly I'm rethinking the whole idea of these batteries in these lights. Doesn't seem like a safe idea to run on Hi in the L0D-CE either, since we seem to talking about ~3C discharge rate here.

Be safe everyone! :twothumbs

anybody know the runtime of the l0d on strobe?
No one has done this to my knowledge, but I remember Chevrofreak had looked at it on the P1D-CE when it came out. As you'll see here, strobe runtime wasn't even as good as Medium (Primary) mode:
https://www.candlepowerforums.com/threads/144407

I expect it's likely similar for the L0D-CE, but haven't tried it.
 
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