Nitecore Explorer (EC1, EC2, EA1, EA2) Round-up Review: RUNTIMES, BEAMSHOTS, VIDEO+

chadvone

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Thank You SB for another great review. I like the EA1 as it is , but the runtimes on lower setting are too low for my tastes. Maybe there will be version .2 that they get the runtimes on low and red increased.
 

ergotelis

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Selfbuilt, i can see something going wrong on your measurements. I think something is not made right and you numbers seem overrated. Let me explain.

Lets take Nitecore EC2. You are using a AW 2200mah, which is quite a "tired battery", but lets guess that it is still performing quite well.
You are mentioning that EC2 outputs 270 lumen stable for 3hours. 3 hours of discharging for an AW 2200, means about 0,7amp to the led. Even in perfect efficiency, which we don't have anywhere, it won't be higher than 0,8amp, without of course counting the fact that this AW won't perform as it did in its first cycles.
According to cree, a xp-g R5, @0,7amp,@25 C has output of 260-280 lumen. Do you get the Point?

If we add the higher temp, maybe almost 70 C on the core, the lumen loss due to reflector and glass, we won't be getting more than 230 lumen from the flashlight. And this is for a top bin led xp-g S2, for example. My estimation, about 200 lumen OTF, for a classic xp-g R5.
I don't own the flashlight, i am going to have it soon.

And this possibly happens for all of your nitecore explorer series flashlights, can't comment for the others models other than those of the same form factor. i bet that also on them, EC1, EA2, EA1 , your results are overrated.
 
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selfbuilt

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Lets take Nitecore EC2. You are using a AW 2200mah, which is quite a "tired battery", but lets guess that it is still performing quite well.
No, I'm afraid you've misunderstood - it is a new battery.

AW still manufacturers and sells 2200mAh cells. In fact, I buy over a dozen new ones every year, usually in batches of 4 every 3-4 months. This is the same for all the other rechargeable cells in my testing. I discard cells after about 40-50 discharge cycles, max (maybe less).

It is fair question to ask for the deailed methodology of my testing. Let me summarize it:

I verify every new battery that arrives to confirm that it performs within the range of early samples (using a standardized set of lights that I run everything though in my lightbox). Capacity outliers are discarded, although that is pretty rare with AW. His cells 2200mAh 18650 and 750mAh RCR protected cells haven been remarkably consistent in rated capacity over time (14500 less so, but still reasonable - there has been a slight increase in capacity over time).

The same is true of my Eneloops. I buy multiple packs of 4xAAA and 4xAA every time they go on sale here, and go through them even faster than Li-ions (probably more like 20-25 cycles on average, maybe less). The reason for that is the occasional over-discharge occurs (i.e. running a light down to off, or nearly there). This is damaging to LSD NiMH - I toss those cells once one of those events occur.

I also maintain an ongoing calibration of lightbox (again using a standardized set of lights, tested at regular intervals). My lightbox design is permanently mounted (i.e., the sensor never moves), and I have determine an internal calibration standard. From inception, I can confirm that there is a <2% drift per year, which I correct for on at least a monthly basis. So the relative output values you see today are entirely consistent with the results from several years ago.

The point is that the internal standard for my lightbox (and all runtime graphs) is tightly controlled and monitored. You can rest assured that results are directly comparable. To use the example of the EC2, the initial turbo output is indeed the same as my samples of the Rofis JR20, Armytek Predator, etc. If I were to run those lights in my lightbox again (with the current calibration), the graphs would be pretty much indistinguishable (I know, because I do this periodically to confirm the calibration). :)

As to the actual lumen estimate, I have never made any claim to its absolute value accuracy. The method I have used to adjust my interally-consistent and calibrated lightbox values to estimated lumens (and note I always refer to them as such) is based on a statisical relationship developed form an extensive series of comparisons, described in detail here:

How to convert Selfbuilt's Lightbox values to Lumens


The point is that the relative value accuracy of my measures remains remarkably high. So if I estimate one light at 270 lumens and another at 300 lumens, you can feel fairly comfortable with the conclusion that the second light is indeed about 10% brighter. But whether or not that is really 240 and 265 lumens (or 300 and 330 lumens , etc, etc.) I cannot say with any certainty. For that, I am relying on all the results of the 150 or comparison points in the analysis above.

Frankly, there is no way anyone without a properly maintained, properly-sized, NIST-certified, calibrated integrating sphere - used under controlled conditions by a knowledgeable and skilled operator - can asert true, absolute accurate lumens. However, as you will see in the analysis above, I think I have gone to more effort than most in trying to make my estimates as good as they can be.

In any case, I still make no claim to the accurate lumen estimate accuracy. But I do assert that the runtime graphs remain an absolutely well-calibrated and internally-consistent relative set of results from my testing, using only new batteries properly examined for relative performance.

If (and when) AW stops making consistent 2200mAh cells (and Sanyo stops making consitent 2000mAh Eneloops), I am certainly going to have a lot of re-testing to do ...

Again, it is perfectly valid and appropriate to question the methodology used by anyone to report relative or absolute values. Some of this is explained on my flashlightreviews.ca website, and I periodically write up posts like this when queried. I hope that clarifies the situation ... happy to explain further if anything isn't clear. But do check out that other thread for the explanation of the lumen estimation.

:wave:

Update: I'm gone back to check the full runtime data for the EC2, and the output on Hi is actually closer to ~255 estimated ANSI lumens (using my method above), not 270. This review was an unsual situation, as I rushed to get the summary tables up before leaving town (and thus didn't have the full runtimes of all models). In the case of the EC2, I did quick manual testing of each level in my lightbox at 30secs, and then did hand calculator conversions - looks like something was a bit off on that one. Normally I do the summary tables last, so have complete traces to work from (and automatic Excel generated formulas, so no user error to worry about). Now that all the runtimes are all completed, I will verify all the values against the excel files to confirm.
 
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ergotelis

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Ok, thanks for all these details, i don't doubt about runtime graphs, just for the lumen estimation method/standard that you have, so, i still insist on that, even if an AW 2200 is new:

"A xp-g R5(even the best ones) is impossible to output 270 lumen for 3 hours from a single 18650 AW 2200" . Is it only me seeing that there is something wrong with this?

For me, either the runtime had to be 2 hours, or the lumen have to be about ~200.

Only a good xp-g2 / xm-l U2 can probably make the numbers selfbuilt posted.
 

regulator

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Fantastic SelfBuilt. That was a great read and really helps understand your method of testing. It also provides a lot of confidence when comparing performance of lights (albeit from a single sample). I always look forward to seeing your testing of a new light I am interested in. I also like being able to pull up charts and numbers from multiple lights that you have tested previously to make comparisons.
 

selfbuilt

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"A xp-g R5(even the best ones) is impossible to output 270 lumen for 3 hours from a single 18650 AW 2200" . Is it only me seeing that there is something wrong with this?
I have now re-verified all the lumen estimate tables based on the actual runtimes in my excel tables. Most of the results were consistent with my initial reports - the only two that were noticeably off were the EC2 estimate on Hi is (now corrected to ~250-255 depending on battery) and Turbo on EA2 (estimate now corrected to ~355 on my scale).

I warrant that still seems high for the EC2, but a number of factors may be in play here. First, that's only the ANSI FL-1 estimate at 30 secs - after a couple mins, output drops to closer to ~240 lumens on the 18650 Hi mode run. Secondly, (as previously discussed) I agree the absolute value of the lumen estimation may be off - the conversion is only as good as the comparator data in the analysis linked to above.

Third is the battery variation. I have looked up which battery that Hi mode was done on - and it is one that tests at the very top end of my accepted range of capacity of AW 18650 cells. In case you are curious, the acceptable capacity variance range that I use for those 18650 cells is +/- 3.5% from average, upon arrival (measured at ~1A draw). I do this because I find that > ~90% of cells I buy fall within that range upon testing (i.e., I don't need to toss too many outliers). FYI, I also track each individual battery for just this purpose, so I can go back to verify anything unusual results.

Another point is that I do not know what the Vf of the emitter on my particular EC2 sample is (not identified, and I've previously noticed it can have a huge effect on runtimes). For that matter, I don't know if the output bin is really a R5 (that's just what Nitecore reports). It's always possible that that is a minimum spec, and they bundle higher output bins when available as well (e.g., S2?). And as always, where in the bin it falls is unknown (although I think we can assume this sample is good one).

The point is that when you put all those variable in play, it's possible (though uncommon), for all the "stars to align" in the same direction, giving unusually high or low performance for a given light, on a given battery, at a given level. That is certainly true when you consider the uncertainty in lumen estimation - it is the one factor that I cannot fully control for, as I am dependent on a comparison to other known results. :shrug:

It also provides a lot of confidence when comparing performance of lights (albeit from a single sample).
I am glad to see your parentheses ;) - yes, the other main limitation here is sample variability. I typically only test n=1 of any given light. I thus have no way to know what the typical variation among samples is, and where mine sits relative to the mean. It is always a mistake to assume "typical" performance from any one sample.

It's important for people to think of all these results statistically. I do what I can to limit additional variability introduced by testing, but the fundamental variation is unknown.
 

jhc37013

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Selfbuilt great job on not only the review but also your responses to the questions about your testing method, the best simply the best.
 

JudasD

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selfbuilt: after your red LED run on the EC1 did you happen to notice what the battery voltage was? Mine ran for alot longer than 2 hours (6 hours to be exact) and my battery voltage was at 3.45 volts. Any thoughts as to why the EC1 would have short LED runtimes compared to the rest of the line?

JD
 

selfbuilt

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selfbuilt: after your red LED run on the EC1 did you happen to notice what the battery voltage was? Mine ran for alot longer than 2 hours (6 hours to be exact) and my battery voltage was at 3.45 volts. Any thoughts as to why the EC1 would have short LED runtimes compared to the rest of the line?
No, I'll have to try another runtime and measure it on mine. The 18650 coming out of the EC2 had its protection circuit tripped, but that one ran for over a week (i.e., a much slower current drain). I'll give the EC1 another try when I get the chance.
 

jhc37013

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Selfbuilt do you have a dark spot in your EC2's hotspot? Mine has a dark spot in the hot spot, I noticed the EA2 has that hybrid type reflector but the EC2 is a regular smooth reflector and I don't have a dark spot in my EA2, not sure why they didn't use the hybrid reflector in the EC2.

Also your EC2 and EA2 have about the same micro mode output ~1.8 lumens but my EC2 is closer the to the low mode of the EA2 I'd say about 10-15 lumens. Now my EA2 seems to be about equal with yours at the ~1.8 lumen count.

Comparing to different light's I have that I know for sure are around ~300-320 lumens then I'd say my EC2 on max is around the 320 mark.
 
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selfbuilt

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Selfbuilt do you have a dark spot in your EC2's hotspot? Mine has a dark spot in the hot spot, I noticed the EA2 has that hybrid type reflector but the EC2 is a regular smooth reflector and I don't have a dark spot in my EA2, not sure why they didn't use the hybrid reflector in the EC2.
It is pretty common to see some sort of dark spot in the center hotspot of XP-G lights with smooth reflectors. In some cases, this can look like a dot right in the center, or a slight dark ring near the center (fancifully referred to as a "nipple" by some here). I didn't comment on it in the review, but my EC2 has a slight dark ring (and my EA2 has slight center dot).

But in both cases, you have to really look for it on a white wall (note for example that I can't see it in the white wall beamshots). Since my samples are no worse than other lights, I didn't bother mentioning it before.

As for the reflector, only my two EC1 samples and original EA1 has noticeable evidence of rings at the base (i.e. "hybrid") - my EA2 and EC2 both seem quite smooth (as does my replacement EA1). Since all lights have the same size head, I suspect this just some variation in reflector manufacture. But I agree, the more "hybrid" pattern is probably better.

Also your EC2 and EA2 have about the same micro mode output ~1.8 lumens but my EC2 is closer the to the low mode of the EA2 I'd say about 10-15 lumens. Now my EA2 seems to be about equal with yours at the ~1.8 lumen count.
Thanks for sharing. That would suggest the abnormally high "Micro" mode is not just limited to my EC1 sample (i.e., it probably a sign of variability more generally across line, affect various samples). My EC2 and EA2 definitely have comparable micro output (as did my EC1 engineering sample - it is just my EC1 shipping sample that was higher).

I hope they are able to lock that down better, as I personally prefer as low as possible for the lowest level (i.e. I would rather take my EC2 with me back into a rainforest, than my shipping EC1 for this reason).

Comparing to different light's I have that I know for sure are around ~300-320 lumens then I'd say my EC2 on max is around the 320 mark.
Yes, it could well be my lumen estimates are off in that range - I had few samples in the ~300-450 lumen range to compare to in my original analysis. But in comparing the few lights >~300 lumens lights that I jad in common with BigChelis, MrGman and TiForce, this lumen esitmate conversion came in pretty consistent to their readings. For example, my 4Sevens G5s (both pre-release and shipping), clocked in at ~290 lumens on Turbo in my lightbox using this method (which is very consistent to what others reported at that time for the initial release). And my EC2 is quite a bit brighter overall. :shrug:

Now that I have a NIST-certified lightmeter, I may start experimenting with building a better integrating sphere and redoing the comparisons that the conversion is based on. No promises, but I'll see if I can spend some time later this summer playing around with it.
 

NiteShift

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Really great review Selfbuilt.

My biggest disappointment with these is the low runtime of the Red SMD LED - only 5 hours for the EA1! Interesting to note the heat/runtime correlation - and also the size/heat/runtime correlation. The smallest light gets the shortest runtime and the the largest light gets the longest (the EA1 being in the middle) Someone living in a cold environment would do better with these lights I guess.

Thanks again SB
 

selfbuilt

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My biggest disappointment with these is the low runtime of the Red SMD LED - only 5 hours for the EA1! Interesting to note the heat/runtime correlation - and also the size/heat/runtime correlation.
Agreed, it is disappointing (both the absolute runtime on some lights, and the wide degree of apparently acceptable variation). Certainly quite happy with my EC2 sample ...

One thing - I have just re-done the red mode runtime on the EC1, and again got ~2hr 45min. This time I measured the voltage of the cell afterwards (after a couple of minutes - it took me a bit of time to notice the light had gone out, so the cell would have had some time to recover). I measured 3.0V exactly. So it looks like my EC1 is running down the cell to close to its protection circuit tripping point.
 

JudasD

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Agreed, it is disappointing (both the absolute runtime on some lights, and the wide degree of apparently acceptable variation). Certainly quite happy with my EC2 sample ...

One thing - I have just re-done the red mode runtime on the EC1, and again got ~2hr 45min. This time I measured the voltage of the cell afterwards (after a couple of minutes - it took me a bit of time to notice the light had gone out, so the cell would have had some time to recover). I measured 3.0V exactly. So it looks like my EC1 is running down the cell to close to its protection circuit tripping point.

This is very interesting that the single red led can discharge the 16340 in almost 3 hours. Mine took 6 hours and the light shut itself off and the battery was still at 3.45v. Something is very weird about the EC1 quality control.

JD
 

selfbuilt

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A question came up about water-proofness in another thread (where a user reported watering entering the head of his EC1).

FYI, I've just popped my EC1 into a glass of water for an hour (with a battery installed and indicator blinking).

Took it out, and absolutely no signs of water penetration anywhere on the light. The head is still perfectly sealed and dry, and no water has entered the battery tube.

Hopefully the reported failure was an exceptional situation (I note Nitecore has already responded in that case with an offer to replace the light).
 

NiteShift

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Having just brought one myself (EA1) I did the same glass of water test and found no signs of leakage. Although as I said in the other thread, I'm not sure how constant exposure to water/dampness may effect the adhesive on the switch sticker and subsequently the switch its self? I feel this could be a weak point for water entry.

I just wanted to mention that my EA1 (unlike Selfbuilt's replacement model) can indeed take protected 14500 cells. Specifically AW's Red Label Cells. There's a bit of side play too, which means there would be room for an even thicker cell.

I plan to try and test the red LED on my sample and see if there is any difference in runtime when compared to selfbuilt's findings. I'll report back asap :wave:
 
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selfbuilt

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Having just brought one myself (EA1) I did the same glass of water test and found no signs of leakage. Although as I said in the other thread, I'm not sure how constant exposure to water/dampness may effect the adhesive on the switch sticker and subsequently the switch its self? I feel this could be a weak point for water entry.
I agree, this is the most likely source of entry for those who experienced it in the other thread. Any damage/lifting of that sticker could allow water into the light.

Note by the way that the IP ratings are not very specific as to terms. IPX8 simply means that the light can handle some depth (>1m) for some period (specified by the manufacturer). It also doesn't necessarily mean that no water can enter (i.e. the minimum spec is that no amount of water enters that can produce a harmful effect on functioning).

But the ANSI FL-1 standard is more specific - the "submersible" rating (which Nitecore supplies for the Explorer series) means meeting the IPX8 standard at a specified depth (2m given in this case) for 4 hours. Note that standard ANSI testing requires 5 samples for immersion tests, and is done with a battery loaded but the light off, and the light functiong tested immediately after the test (and again 30 mins later). It also specifies that there must be no ingress of water in any area that contains unprotected electrical components or light sources. So ANSI FL-1 is a more rigourous interpretation of IPX8 (which is really a minimum rating).

Personally, I would expect the explorer lights to be at least as water-resistant as any other make or series. But I can understand the concern that not all samples may meet the actual ANSI FL-1 submersible standard of the IPX8 rating (i.e., there's at least two reports of water ingress under presumably less stringent conditions).
 
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Phil Ament

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I agree, this is the most likely source of entry for those who experienced it in the other thread. Any damage/lifting of that sticker could allow water into the light.

Note by the way that the IP ratings are not very specific as to terms. IPX8 simply means that the light can handle some depth (>1m) for some period (specified by the manufacturer). It also doesn't necessarily mean that no water can enter (i.e. the minimum spec is that no amount of water enters that can produce a harmful effect on functioning).

But the ANSI FL-1 standard is more specific - the "submersible" rating (which Nitecore supplies for the Explorer series) means meeting the IPX8 standard at a specified depth (2m given in this case) for 4 hours. Note that standard ANSI testing requires 5 samples for immersion tests, and is done with a battery loaded but the light off, and the light functiong tested immediately after the test (and again 30 mins later). It also specifies that there must be no ingress of water in any area that contains unprotected electrical components or light sources. So ANSI FL-1 is a more rigourous interpretation of IPX8 (which is really a minimum rating).

Personally, I would expect the explorer lights to be at least as water-resistant as any other make or series. But I can understand the concern that not all samples may meet the actual ANSI FL-1 submersible standard of the IPX8 rating (i.e., there's at least two reports of water ingress under presumably less stringent conditions).



By the way I just thought that I would add that in my EC1 User Manual it very clearly states the following, and I quote:


Waterproof in accordance with IPX-8 (2 meters submersible)


I would also like to add that I currently have five different brand new EC1's to directly compare to each other, and there appears to be a rather large variance in nearly every aspect of them, including the output levels, beam profiles, reflectors, run times, voltage readout accuracy and various other details too. There also appears to be some sort of artefacts (if that is the right word for it) or small shadows in the hot spots, however the shape and pattern of it differs greatly with each light. When I had a close look at the reflectors in each of them I noticed that there were reflections of some sort of foreign material in them. I then had an even closer look at them, first with a magnifying glass and then a jeweller's loupe, and each one of them has a considerable amount of dust/grit on the reflectors and I also noticed that they also seem to have dirt/grit and several very distinct black spots on the domes of all of the LED's, and which sort of looks a little bit like pepper although I am not really sure what it actually is. I then did the same thing with several of my other similar quality lights (JETBeam, Fenix, SureFire, Dereelight, Sunwayman) and all except for one were perfect (Sunwayman M10R with a large smudge in the middle of the dome) and they did not have any such similar traits.

I also must say that while I believe the Explorer series have the potential to be really wonderful flashlights, I am extremely disappointed in the apparent lack of any acceptable standards in their construction and quality control! Oh, and I haven't even been game to try the water dunking test yet!
 
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roadkill1109

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Selfbuilt, I noticed the lux disparity between the RCR123 and the 14500 and the 18650, since they have identical heads and essentially the same voltage for the lithium ion cells, wouldnt the output be identical? What could be causing this disparity?

I had my heart on the EA1 and run it with a 14500 to reap the benefits of having a smaller light but with good throw, but with the lux ratings you posted, it just turned me right off. My Quark AA w/14500 and Turbo X head can do better. :)

Anyways, after reading this review, gave me a better idea to just purchase the SWM C20C. :)

Thanks again Selfbuilt! As always, we count on your reviews (and Marshall's too) before buying our next lights!
 
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