Klarus ST10 (1xAA, XP-G R5) Review: RUNTIMES, BEAMSHOTS PICS, and more!

selfbuilt

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Warning: pic heavy, as usual. :whistle:

ST10002.jpg


Specifications:
  • LED: Cree XP-G R5
  • Lighting mode: 140 lumens (1.5hrs) - 60 lumens (4.8hrs) - 12 lumens (25hrs) - 2 lumens (83hrs)
  • Flashing modes: SOS - (60 Lumen, 13.4hrs) - Beacon (60 Lumens, 70hrs) - Variable frequency strobe (140 Lumens, 3hrs)
  • Runtimes based on SANYO 2500mAh Ni-MH battery.
  • Working Voltage: 0.9V-1.8V
  • Battery: 1pc 1.5V AA (Alkaline, Ni-MH, Lithium)
  • Tactical tail switch for power on and off with momentary activation
  • Side switch for adjusting brightness output
  • Rotate the flashlight head to access hidden modes (Super Low, SOS, Beacon)
  • Strobe access: Press and hold the side switch for 0.5 seconds in any mode
  • Lens: Toughened ultra-clear glass
  • Material: Aircraft grade aluminum
  • Dimensions: 107mm (Length) x 25.3mm (Head) x 20mm (Body)
  • Net weight: 53g (Excluding battery)
  • Waterproof to IPX-8 Standard
  • Intelligent memory function (memorizes the last used lighting mode)
  • High-efficiency digitally regulated output - maintains constant brightness
  • Reverse polarity protection
  • One hand operation
  • Included accessories: holster, lanyard, body clip, two spare o-rings, and a rubber switch boot
  • Estimated MSRP ~$58
Kalrus is a new maker on the scene, and the ST10 is their first 1xAA model. Note the specs show support for standard batteries (NiMH/Alkaline/L91 lithium) only – 14500 is not supported.

ST10003.jpg

ST10001.jpg


Packaging is fairly standard, but the light comes with a good number of extras. Inside the cardboard box with plastic insert is the light, manual, spare o-rings, extra boot cap, wrist strap, pocket clip, and belt holster (with closing flap).

ST10018.jpg

ST10015.jpg

From left to right: Duracell AA, Klarus ST10, Fenix LD10-R4, ITP SA1, Zebralight SC51, Nitecore D10SP

ST-10: Weight: 53.0 g (no battery), Length 107.6mm x Width 22.5mm (bezel) 25.2mm (near switch)

ST10004.jpg

ST10007.jpg


Build quality is excellent. Note the square-cut threads at both ends of the battery tube. Screw threads are anodized at the tailcap for lock-out. :thumbsup:

The switches both have a good feel. The tailcap switch is a typical forward clicky, and the side switch feels like an electronic switch (but with better than typical feedback).

My sample tailstands, but barely (i.e. it is quite wobbly). I suspect some adjustment of the clicky might help. I note that my Klarus NT20 sample (currently in testing) tailstands with virtually no wobble.

Light feels reasonably solid, if a bit top-heavy. Knurling is not very aggressive, but there are a lot of body ridge details to help with grip.

Anodizing is excellent on my sample, no chips in the flat black finish (HA = type III). Lettering is sharp and clear, nice and bright against the black background.

ST10009.jpg

ST10008.jpg


Clip seems to be fairly sturdy and good quality. It holds onto the light well, and can be positioned for bezel-up or bezel-down carry. But with all clips of this sort, these is always a risk the light might catch on something and be pulled off. The included holster seems good quality, and comes with a closing flap.

ST10006.jpg

ST10013.jpg


The ST10 features the Cree XP-G R5, with a medium textured orange peel (MOP) deep reflector.

Which brings us to the requisite white wall hunting ;). All lights are on Hi on Sanyo Eneloop, about ~0.75 meter from a white wall (with the camera ~1.25 meters back from the wall). Automatic white balance on the camera, to minimize tint differences.

ST10-Beam001.jpg
LD10R4-Beam001.jpg

7G1-Beam001.jpg
MiniAA-Beam001.jpg


ST10-Beam002.jpg
LD10R4-Beam002.jpg

7G1-Beam002.jpg
MiniAA-Beam002.jpg


ST10-Beam003.jpg
LD10R4-Beam003.jpg

7G1-Beam003.jpg
MiniAA-Beam003.jpg


ST10-Beam004.jpg
LD10R4-Beam004.jpg

7G1-Beam004.jpg
MiniAA-Beam004.jpg


From now on, all my beamshots will be taken in this standard configuration, to facilitate comparisons.

As you can see, the ST10 has a nice and reasonably smooth beam for this class. Scroll down to my Summary Tables for more specifics on output.

User Interface

The UI is fairly unique on these Klarus lights.

Turn the light on by pressing the tailcap clicky (press for momentary on, click for locked on).

With the head fully tightened, you get the regular modes. Press and release the side switch to change output levels. The output mode will change in the following sequence Lo > Med > Hi, in repeating order. The light will memorize the last mode used, and return to it upon re-activation.

With the head loosened (turn 1/8 turn counter-clockwise), you get the "Hidden" modes. Using the side switch, the output sequence is Super Lo > SOS > Beacon, in repeating order. Note there is no memory feature for the Hidden modes – the light will always come on in Super Lo (aka moonlight) upon activation with the head loosened.

Strobe is accessed from either mode state by pressing and holding the side switch for longer than half a second. As long as you hold the switch down, you will get a constant strobe mode. Release the switch, and a variable frequency strobe continues until you turn off the light or change modes (use the side switch to change to modes). Scroll down for the frequencies.

An interesting variant on the classic Fenix/4Sevens interface.

PWM and Strobe

The ST10 is current-controlled on its regular output modes (Lo, Med, Hi). It is just the "Super Lo" (aka moonlight) mode that uses PWM:

ST10-SuperLo.gif


PWM on Super Lo is 120 Hz.

This is thus similar to the Zebralights, where current-control is used for regular modes (for max efficiency), and PWM is used for "moonlight" (for extended runtime at much lower output). :thumbsup:

ST10-StrobeHold.gif


If you press and hold the side switch, the light strobes at a constant frequency of 18.4 Hz. Once you release the switch, however, the light continues to strobe at an oscillating pair of frequencies:

ST10-Strobe.gif


The light spends ~1.8 secs at 18.4Hz, followed by the same length of time at 7.2Hz, in a reoccurring cycle. Not sure of the point of this, but it is certainly annoying! :green:

Testing Method:

All my output numbers are relative for my home-made light box setup, a la Quickbeam's flashlightreviews.com method. You can directly compare all my relative output values from different reviews - i.e. an output value of "10" in one graph is the same as "10" in another. All runtimes are done under a cooling fan, except for any extended run Lo/Min modes (i.e. >12 hours) which are done without cooling.

I have recently devised a method for converting my lightbox relative output values (ROV) to estimated Lumens. See my How to convert Selfbuilt's Lighbox values to Lumens thread for more info.

Throw/Output Summary Chart:

Effective November 2010, I have revised my summary tables to match with the current ANSI FL-1 standard for flashlight testing. Please see http://www.sliderule.ca/FL1.htm for a description of the terms used in these tables.

1AA-FL1-Summary1.gif


The max output of the ST10 is very similar to the Fenix LD10-R4 (with a slight bump in output, likely due to the R5 emitter). Super Lo is much lower, thanks to the PWM (roughly equivalent to Lo2 of the Zebralight SC51).

I'll have more to say on output levels after the runtimes … :whistle:

Output/Runtime Comparison:

ST10-HiL91.gif


ST10-HiEne.gif

ST10-MedEne.gif

ST10-LoEne.gif


ST10-HiAlka.gif

ST10-LoAlka.gif


Output/runtime performance is outstanding. :eek:oo:

Basically, the ST10 performs at least as well as the Fenix LD10 would do with a R5 instead of an R4. More than that, the output levels of the ST10's Lo/Med/Hi map exactly to the LD10 in the following way:

ST10 Hi = Fenix LD10-R4 Turbo
ST10 Med = Fenix LD10-R4 Hi
ST10 Lo = Fenix LD10-R4 Lo

Basically, you are missing the LD10's Med mode, but you get the equivalent of the 4Sevens Quark Moonlight mode instead.

I can thus only conclude that the ST10 is using a hybrid of the Fenix LD10 circuit (sans Med mode) combined with PWM for Super Lo/Moonlight.

Potential Issues

My ST10 sample is a bit wobbly, but my NT20 sample tailstands with no problem. Adjusting the switch/boot cover may help in cases where tailstanding is not perfect on these Klarus lights.

Need to switch grip to change modes after turning on (i.e. rear tailcap for on-off, side switch for modes).

Strobe can be accidentally accessed if you hold down side switch too long while trying to change modes (i.e. greater than 0.5 secs).

Preliminary Observations

I seem to be seeing a rash of new makers lately - with surprisingly mature builds and circuit designs. The Klarus ST10 is another good example of this phenomenon – a solid light, with excellent performance and a somewhat novel interface. :)

The physical build of the light suggests a quality manufacture. There are a lot of nice design touches, and the light feels reasonably well balanced (maybe a little top heavy, accentuated somewhat by the narrower battery tube). Switch design seems good at both ends, with a good feel to both the rear on/off forward clicky switch and side level-changing electronic switch.

Mode changing is a little unusual, but should quickly become familiar to those used to the regular Fenix/Olight/4Sevens series (i.e. the head tight/loose for different mode sets). The main difference is the use of the side switch to select the levels within each set instead of the tailcap (i.e. like the ITP SA/SC series, or Lumapower MVP).

I found the UI quickly became intuitive (e.g. upon activation, head loose gives Super Lo, head tight for a memorized and selectable Lo/Med/Hi). I like the fact that you can ignore the various blinking modes if you don't want to see them. One quibble here – 0.5 secs isn't very long, and you may strobe yourself while changing output levels if you don't release the side-switch fast enough. Also, what's up with the oscillating two-freq strobe mode? :thinking: I wish makers would dispense with uber-annoying strobe modes, and simply give us a nice, simple slow (~1-2 Hz) signaling strobe. :sigh:

Output/runtime efficiency is one area where this light really performs. In fact, the specific output/runtime characteristics on Lo/Med/Hi are identical to the current-controlled Fenix LD10-R4's Lo/Hi/Turbo. :eek:oo: Coupled with the PWM-based Super Lo/Moonlight, you really get a good combination here.

But another quibble – I can understand dispensing with the Fenix-like Med on the other models in the Klarus line, but on the ST10 (like the LD10) this means you will see little difference between its two highest output levels. I don't know what the 2xAA Klarus is like (maybe it uses the same head as the ST10, like the Fenix LD20/LD10?), but I would have liked to seen levels spaced differently on the 1xAA version. :shrug:

All-in-all, this is an impressive first offering from a new manufacturer. I'm particularly glad to see the efficiency of a current-controlled Fenix-like circuit integrated with a Moonlight/Super Lo mode (although the latter is PWM-based in this case). Along with a number of innovative design features, I imagine Klarus will be attracting a fair amount of attention here.

----

ST10 provided by goinggear.com for review.
 
Last edited:

selfbuilt

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Written by tandem on 12-03-2010 06:28 PM GMT

Also, what's up with the oscillating two-freq strobe mode? I wish makers would dispense with uber-annoying strobe modes, and simply give us a nice, simple slow (~1-2 Hz) signaling strobe.
You can say that again. Small lights like these are much more likely to be used by hikers and cyclists than a SWAT team! You can say that again. Small lights like these are much more likely to be used by hikers and cyclists than a SWAT team!

Very impressive output-runtime performance. The ante continues to be upped. I wonder if Fenix has something in store or if they are simply going to coast on the LD10/20 for another year.
Written by GoingGear.com on 12-03-2010 07:17 PM GMT

tandem said:
You can say that again. Small lights like these are much more likely to be used by hikers and cyclists than a SWAT team!
Eh, you'd be surprised. Strobe is the #2 request after max output from people outside of CPF and people outside of CPF greatly outnumber those on it. I still love you guys though. Eh, you'd be surprised. Strobe is the #2 request after max output from people outside of CPF and people outside of CPF greatly outnumber those on it. I still love you guys though. :D
Written by selfbuilt on 12-03-2010 08:21 PM GMT

GoingGear.com said:
Eh, you'd be surprised. Strobe is the #2 request after max output from people outside of CPF and people outside of CPF greatly outnumber those on it. I still love you guys though. :D
I'm still with tandem on this one. I'm still with tandem on this one. ;)

Out of curiosity, do those requests specify what kind of strobe? 1-2Hz is *very* different from the common 10-18Hz "tactical" strobes you find on most lights these days. It people are looking for a biking light, or something to signal ongoing cars while out for a walk, I would think a slow signaling strobe is what most people would want. I've yet to meet too many folks in the real world (outside CPF) who want seizure-inducing strobe levels. :rolleyes:

This is one area where I think Zebralight got it right (e.g. on the SC50/SC51 lights).
Written by tandem on 12-03-2010 10:01 PM GMT

GoingGear.com said:
Eh, you'd be surprised. Strobe is the #2 request after max output from people outside of CPF and people outside of CPF greatly outnumber those on it.
I didn't say no strobe, just not a seizure inducing strobe. I didn't say no strobe, just not a seizure inducing strobe.

I'm with Selfbuilt all the way here... I want a 2 - 3 Hz strobe (call it a blinkie if you will), not a "tactical" strobe in a light that most of the time will never see tactical use in anyone's hands -- I'm speaking of 1 and 2 AA lights and all AAA lights.

Since LEOs actually do buy lights in the class of the TK11/12 (as an example), I can see marketing an integrated light of that sort having a strobe with a more tactically useful pattern.

One example where tactical strobes are not often useful is for cycling. Cyclists can't use many lights with tactical pattern strobes in the dark because they are too distracting both to them and to oncoming motorists. Worse, many lights on strobe run at full output or not far from it. I only use my "tactical" fast strobes on the bike in broad daylight and gloomy days, never in the dark. If you could dial down the output power significantly for a tactical strobe, then it could be useful as a marker on a bike or pedestrian. Yet a 2Hz strobe would be useful at almost any output level.

Maybe I'm way off the mark but "tactical" strobes on lights for the masses seems to me to be an idea that looks much better on paper than in practice. If makers just want ensure buyers can "check off that box" on their requirements list, a 2Hz strobe would allow them to do that and make it overall a more useful light.
Written by Burgess on 12-03-2010 11:02 PM GMT

Very interesting flashlight.

Another fine review, SelfBuilt.

:goodjob: :kewlpics: :thanks:

_
Written by GoingGear.com on 12-03-2010 11:29 PM GMT

selfbuilt said:
I'm still with tandem on this one. ;)

Out of curiosity, do those requests specify what kind of strobe? 1-2Hz is *very* different from the common 10-18Hz "tactical" strobes you find on most lights these days. It people are looking for a biking light, or something to signal ongoing cars while out for a walk, I would think a slow signaling strobe is what most people would want. I've yet to meet too many folks in the real world (outside CPF) who want seizure-inducing strobe levels. :rolleyes:

This is one area where I think Zebralight got it right (e.g. on the SC50/SC51 lights).
No, they are looking for a fast, seizure inducing strobe, not a slow one. I would consider a slow 1-2 hz one a beacon, not a strobe. No, they are looking for a fast, seizure inducing strobe, not a slow one. I would consider a slow 1-2 hz one a beacon, not a strobe.

I know I live in the south and we like our guns and other crippling weapons here, but I get the strobe question from people all over the country and even the world. Trust me, a lot of people want a fast strobe. There seems to be a lot of appeal in a light that doubles as a self defense tool. The one that I have never, ever had anyone specifically request is SOS.

Regarding AA lights for tactical uses, that is another top request from LEOs around here. A lot of the departments in the area give their officers free AAs instead of CR123s, so they look for AA lights. One of the local fire departments is outfitted with Fenix LD20s.
Written by Russ Prechtl on 12-04-2010 11:15 AM GMT

+1 on a great review! Thanks. Another great one for the collection. :thumbsup:

BTW - I also hate the fast strobes. :thumbsdow
Written by Acid87 on 12-04-2010 11:44 AM GMT

As always a really well done review in depth and to the point. I was really intrigued by the new Klarus lights but was too scared to make the plunge. Thanks think I know what im getting for xmas! :thumbsup:
Written by RBWNY on 12-04-2010 07:13 PM GMT

Hi! Loooooooong-time browser, first-time poster!! I'll skip the formal introductions for now, by simply announcing that due to the excellent review of the ST10... I just ordered an ST20 :naughty:

I'll post my findings, and perhaps compare it to my EagleTac P20A2 MKII, which seems similar in brightness and build quality. I have a feeling though, that I'm gonna like the Klarus better!! (I hope)
 

selfbuilt

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Written by selfbuilt on 12-05-2010 10:02 AM GMT

Glad you are all enjoying the review. :grouphug:

GoingGear.com said:
I know I live in the south and we like our guns and other crippling weapons here, but I get the strobe question from people all over the country and even the world. Trust me, a lot of people want a fast strobe. There seems to be a lot of appeal in a light that doubles as a self defense tool.
Interesting. And no doubt, my perspective is shaped by the fact that I'm a Canadian (not too many firearms up here). Interesting. And no doubt, my perspective is shaped by the fact that I'm a Canadian (not too many firearms up here). ;) But I would like to see fast beacon (i.e. 1-3 Hz), overall the more common slow beacon (i.e. 0.1 Hz) or fast strobe (>10 Hz).

Whenever I show my lights around to the un-initiated, the fast strobe is always what initially "impresses" them the most (followed by a continuously-variable interface). But when asked what model they would prefer for their own use, they invariably want something with a small number of constant output modes, and maybe a blinking/beacon mode. I suppose perhaps the difference is that these folks wouldn't be surfing the web looking for dedicated flashlight dealers. So I can see there would some demand for "tactical" strobes from the high-end flashlight crowd.

The one that I have never, ever had anyone specifically request is SOS.
That I can believe! That I can believe!

Regarding AA lights for tactical uses, that is another top request from LEOs around here. A lot of the departments in the area give their officers free AAs instead of CR123s, so they look for AA lights. One of the local fire departments is outfitted with Fenix LD20s.
Hmm, another interesting cultural difference. I'm always checking out the gear on any LEO/EMTs I see, and notice they tend to carry Pelicans/Streamlights/Mags, often the models with dedicated chargers (likely NiCd, ugh). Stingers seem especially prevalent on EMTs for some reason. A number carry what I'm guessing are their own personal 2xCR123A-based light. I wouldn't be surprised if a number are also carrying personal AA-based lights as a backup (e.g. on their belts). But again, the few I've actually spoken to about it have told me they don't use strobe modes at all (this later group is a small sample size, I admit). Hmm, another interesting cultural difference. I'm always checking out the gear on any LEO/EMTs I see, and notice they tend to carry Pelicans/Streamlights/Mags, often the models with dedicated chargers (likely NiCd, ugh). Stingers seem especially prevalent on EMTs for some reason. A number carry what I'm guessing are their own personal 2xCR123A-based light. I wouldn't be surprised if a number are also carrying personal AA-based lights as a backup (e.g. on their belts). But again, the few I've actually spoken to about it have told me they don't use strobe modes at all (this later group is a small sample size, I admit).
 

selfbuilt

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Written by LetThereBeLite on 12-05-2010 10:07 AM GMT

Great review Selfbuilt!

The Klarus ST10 was my first light purchase. It was my introduction to 'expensive' LED flashlights. And I put expensive in quotes because flashlights above $10 are expensive to normal users--such as my wife. :)

I didn't know how good the Klarus ST10 was until I purchased the Fenix LD10 and the Jetbeam Jet-1 Pro v3.0. I had assumed Klarus was a no name light and that Fenix and Jetbeam would be so much nicer. LOL. I was wrong. I actually like the Klarus the most because of its UI and because of its strobe.

I'm definitely with GoingGear. I want a powerful, massive seizure inducing stun strobe to surprise and shock any would be mugger/attacker from invading my space. I don't want a weak, slow pulsing signal flash. I think Klarus did an excellent job in having dual frequency, as oppose to a single frequency strobe. It's even more 'annoying' than a single frequency strobe. :nana:

And best of all--what I find most useful--is the IMMEDIATE access to this seizure inducing strobe by pressing and holding the side clicking for 1/2 second. I find those strobes that are hidden in sub menus or requiring twists or multiple clicks to be ineffective at best and completely useless at worst during an emergency when I need it the most. The Klarus allows for easy, immediate access to strobe anytime by pressing the side clicky for 1/2 second. This is one of the biggest PROs for its Klarus' UI, IMO.

Having said that, there is an immediate negative to the way Klarus implemented its strobe as well. As it is, I have to turn on the light by the tail clickie, then switch to the side clickie to engage the strobe. That basically requires two handed operation or some very dexterous maneuvering to quickly engage the strobe. Once again, in an emergency, it's confusing and time confusing to engage the strobe given the two handed operation. It would have been better if strobe could be immediately and directly accessed from power off to blazing strobe in .5 second, as oppose to first turning on with end switch and then accessible via side switch.

But overall the ST10 is great LED light. A lot better than my first impression when I didn't have any lights with which to compare. Now I can compare and I like the ST10 quite a bit.

I made a little video last night--incidentally before I saw this thread--and I uploaded it to youtube to share with you CPF readers. It a short side-by-side comparison video of the Klarus ST10, Fenix LD10 and the Jetbeam Jet-1 Pro v3.0. By comparison I don't mean a full review of features; I mean a visual side-by-side comparison of the lights so you can see the shape/size difference between the three. Enjoy! :)
Written by LetThereBeLite on 12-05-2010 10:21 AM GMT

GoingGear, sorry for not mentioning your outfit in my review. As I mentioned two other retailers, I should have mentioned you too. :) My bad. LOL
Written by selfbuilt on 12-05-2010 01:56 PM GMT

LetThereBeLite said:
I didn't know how good the Klarus ST10 was until I purchased the Fenix LD10 and the Jetbeam Jet-1 Pro v3.0. I had assumed Klarus was a no name light and that Fenix and Jetbeam would be so much nicer. LOL. I was wrong. I actually like the Klarus the most because of its UI and because of its strobe.
Thanks for sharing. One of reasons I post my reviews here on CPF, and not on my own website, is that I think the trail of users' posts that follow are often invaluable. I encourage everyone to share their views and experiences on all the lights I review. Thanks for sharing. One of reasons I post my reviews here on CPF, and not on my own website, is that I think the trail of users' posts that follow are often invaluable. I encourage everyone to share their views and experiences on all the lights I review. :)

In regards to your comment above, I think its fair to say that the quality of this light is up there with the more established makers. When it comes to these sorts of manufacturers, I generally recommend people choose lights on the basis of features sets, performance and UI.

One thing I would like the emphasize again is the relative efficiency of my ST10 sample - it performs as well as my LD10-R4 sample (taking into account slightly better runtime on the ST10 due to the R5 emitter). While I think the strobe discussion is valuable, it took off from one sentence in a >1600 word review. :laughing: There's a lot more to this light that is worth discussing.
Written by tandem on 12-05-2010 02:21 PM GMT

Nice video LetThereBeLite! Forward clickies with momentary activation are a hot button for me (pun intended); I wish more lights had these. I'm not convinced I like the idea of two-buttons on flashlight, especially one this small. My concern is regarding durability - two moving parts to go wrong, not just one; two points of water or material ingress, two boots which can fail. Perhaps the click-load being distributed between two switches will help in this regard. But from a usability perspective, I'd prefer to control the light with one hand.

Unfortunately in small lights you don't often find a forward-momentary clicky with output stage switching.

I'm really impressed with the runtimes, almost impressed enough to overlook the two switches.

My last word on the strobe: it wouldn't stop me from buying this light. Other factors might, but runtimes or strobe would not be among them.

selfbuilt - are there any build aspects of this light that make you want to think it was produced in the same factory (or by the same designer) as the Zebralight flashlights? The head detail on the side of the front clicky is somewhat familiar looking, as is the front clicky visual appearance itself.
 

selfbuilt

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Written by selfbuilt on 12-06-2010 06:23 PM GMT

tandem said:
selfbuilt - are there any build aspects of this light that make you want to think it was produced in the same factory (or by the same designer) as the Zebralight flashlights? The head detail on the side of the front clicky is somewhat familiar looking, as is the front clicky visual appearance itself.
Hmmm, hard to say. Although the electronic switch feel is (superficially) similar, the overall design doesn't really remind me of Zebralight. But it's virtually impossible to know from the outside - the relationship between Chinese manufacturers is complex, and there is a lot of contracting out work. Hmmm, hard to say. Although the electronic switch feel is (superficially) similar, the overall design doesn't really remind me of Zebralight. But it's virtually impossible to know from the outside - the relationship between Chinese manufacturers is complex, and there is a lot of contracting out work. :shrug:

I'm more confident in thinking the circuit designer is related to Fenix somehow, given the runtime traces. As for the rest, your guess is as good as mine!
 

selfbuilt

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Written by bodhran on 12-07-2010 09:39 AM GMT

Great Review Selfbuilt. My wife was looking over my shoulder while I was reading this and decided that this was the light for her. Surprised me, because she has never showed much of an interest in my flashlights. That's one Christmas present out of the way. *lol* I just hope she shares as I kind of like this one too.
Written by selfbuilt on 12-07-2010 05:15 PM GMT

bodhran said:
Great Review Selfbuilt. My wife was looking over my shoulder while I was reading this and decided that this was the light for her. Surprised me, because she has never showed much of an interest in my flashlights. That's one Christmas present out of the way. *lol* I just hope she shares as I kind of like this one too.
That's funny - another member also told me he was going to pick one of these up for his wife (the ST20, for the extra runtime of 2xAA). I suspect the interface will find favor with the casual user - especially anyone already familiar with the basic Fenix/4Sevens/olight/ITP user interfaces. That's funny - another member also told me he was going to pick one of these up for his wife (the ST20, for the extra runtime of 2xAA). I suspect the interface will find favor with the casual user - especially anyone already familiar with the basic Fenix/4Sevens/olight/ITP user interfaces.
Written by RBWNY on 12-08-2010 08:03 PM GMT

Has anyone noticed?

Light-Reviews.com has just reviewed the ST10 & 20 lights. But they're claiming that the instructions include errors! :eek:oo: First and foremost, is that the super-low mode found within the blinking modes, is IDENTICAL to the "regular" low-mode... 9 for the ST10 & 12 for the ST20. Could it be their samples were bad?

This differs greatly from selfbuilt's synopsis.
Written by Light1 on 12-09-2010 01:44 AM GMT

Very Nice Reivew. :) Iam New here so im glad to be apart of a nice Forum. :)
Written by LetThereBeLite on 12-09-2010 03:46 AM GMT

RBWNY said:
Has anyone noticed?


Light-Reviews.com
has just reviewed the ST10 & 20 lights. But they're claiming that the instructions include errors! :eek:oo: First and foremost, is that the super-low mode found within the blinking modes, is IDENTICAL to the "regular" low-mode... 9 for the ST10 & 12 for the ST20. Could it be their samples were bad?

This differs greatly from selfbuilt's synopsis.
Can you provide a link to the review? As I have a ST10, I can categorically state that it certainly is Can you provide a link to the review? As I have a ST10, I can categorically state that it certainly is NOT the case that low and ultra low are the same on my ST 10. There is a very noticeable difference between the low and ultra low output. I use my ST10 on a daily basis and I use the ultra low often. If what you're relaying with regards to a review by light review . com is correct--as I haven't seen the review myself I can't directly confirm/refute--then they must have received a malfunctioning sample.
Written by RBWNY on 12-09-2010 01:06 PM GMT

LetThereBeLite said:
Can you provide a link to the review? As I have a ST10, I can categorically state that it certainly is NOT the case that low and ultra low are the same on my ST 10. There is a very noticeable difference between the low and ultra low output. I use my ST10 on a daily basis and I use the ultra low often. If what you're relaying with regards to a review by light review . com is correct--as I haven't seen the review myself I can't directly confirm/refute--then they must have received a malfunctioning sample.
Yep, it seems very strange... but here's the link. Yep, it seems very strange... but here's the link.

http://light-reviews.com/klarus_st10/
 

selfbuilt

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Written by selfbuilt on 12-09-2010 03:30 PM GMT

FYI, the Klarus NT20 I currently have in testing also has a very noticeable difference between Lo and Super Lo.

For the ST10 tested in this review, I would estimate the Lo to be ~10-11 lumens, and the Super Lo to be ~1 lumen.

The physical dimensions of my sample were also measured with a digital caliper and digital scale, and are very consistent with reported specs.

The manual with both my ST10 and NT20 are correct in terms of the mode sequence. They are both listed as "High-Low-Mid" (which is another way of saying "Low-Med-High", since the light continues in repeating loop).
 

selfbuilt

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Written by LetThereBeLite on 12-09-2010 05:08 PM GMT

RBWNY said:
Yep, it seems very strange... but here's the link.

http://light-reviews.com/klarus_st10/
Ok, I read it. The review definitely contradicts my ST10. Low and Ultra Low output is very noticeably different on mine. Ok, I read it. The review definitely contradicts my ST10. Low and Ultra Low output is very noticeably different on mine.
Written by RBWNY on Unknown

Since I was not able to begin a new thread, I'll just add to this by reporting on the arrival of the Klarus ST20 I ordered. :party:

So far I like it alot. The size and feel are good, as are the switches. I appreciate the ability to tail-stand, even with the momentary tail switch! The bezel-mounted mode switch works very well and has just the right amount of pressure. The only issue I can see with that, is working in darkness, putting the light down, then picking it up and not finding that switch in an instant (since the light may be turned to the opposite side). What would've been GREAT, would be to have a glow in the dark ring around the button. One other weak point is the metal clip. When it's attached, it's not too sturdy and swivels around while attached. It certainly does not have the grip that a Quark clip has! Although when attached to a side pocket, I don't see it moving or becoming un-clipped without notice.

The brightness levels including the "super-low" (yes it's there) all work well. Overall brightness is very similar to the EagleTac P20A2 MKII. The variable strobe is also kinda cool, albeit not 100% necessary.

At another time, I'd consider getting the NT10 perhaps or maybe the ST10. :)
 

selfbuilt

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The main review post has been updated with the final review text.

The thread discussions have been fully restored from the search engine cache data (thank you tandem!).

Please carry on! :)
 

coachclass

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Selfbuilt,
I'm surprised the Klarus only ran for 2 hours at medium mode. The Zebra so much more efficient (at half the lumens, but over 3 times the run time)

In high mode with the eneloop, the zebra seems to out perform for runtime at about the same lumens as the Klarus. Although the caption saids 1hr26 for Klarus and 1hr37 for Zebra, the zebra graph just looks farther ahead.

What do you think of the relative efficiency between the Klarus and the Zebralight? Out of the batch, I would pick these two as the front runners for efficiency (runtime vs lumens). But the Zebralight still seems more efficient than the Klarus.
 

selfbuilt

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I'm surprised the Klarus only ran for 2 hours at medium mode. The Zebra so much more efficient (at half the lumens, but over 3 times the run time)
Ah, but that's not half the lumens on Med - it's a third. My relative lighbotx output scale is not linear for lumens. If you do the power reationship conversion factor described in the method section of my review, you will see the difference is actually more like ~105 lumens (for ST10) compared to ~35 lumens (for ZL). You really can't make meaningful overall light efficiency estimates with a 3-fold output difference, as emitters run much more efficiently as lower output.

In high mode with the eneloop, the zebra seems to out perform for runtime at about the same lumens as the Klarus. Although the caption saids 1hr26 for Klarus and 1hr37 for Zebra, the zebra graph just looks farther ahead.
Thanks, I'll fix the caption the next time I have my data files open. But again, I wouldn't consider the lumen level to be so equivalent. The ST10 is somewhat in-between the ZL Hi1 and Hi2, and runs very well for the class. It is just that the ZL is exceptionally good for this class at its high output levels - likely because ZL specifically adjusted the circuit to optimize for NIMH.

It's hard to know how they would compare at the lower levels (which I don't test because of time involved, and greater variability due to small changes in emiter Vf). But my experience tells me the Klarus/Fenix circuits would likely have the advantage over the PWM-based ZL (even with its NiMH optimizations) at low-level outputs.

What do you think of the relative efficiency between the Klarus and the Zebralight? Out of the batch, I would pick these two as the front runners for efficiency (runtime vs lumens). But the Zebralight still seems more efficient than the Klarus.
Both are exceptionally good performers in this class. Honestly, I wouldn't base a purchasing decision on minor differences in efficiency - I would go with build and UI preference in this case.
 

Mikellen

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Hi selfbuilt, you mentined that the Klarus has an electronic switch. Will that mean that the Klarus has "parasitic drain" on the battery?
If so do you know how much? For example, Zebralight acknowledges their lights with electronic switches have "parasitic drain" and provides the number of years it would take to drain the battery.

Thanks.

Also in your low mode Duracell alkaline runtime graph in this thread and the Xeno E03 thread, the Klarus is stated as 2 hrs. 49 minutes. Should that read 20 hrs. 49 minutes?
 
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selfbuilt

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Hi selfbuilt, you mentined that the Klarus has an electronic switch. Will that mean that the Klarus has "parasitic drain" on the battery?
If so do you know how much? For example, Zebralight acknowledges their lights with electronic switches have "parasitic drain" and provides the number of years it would take to drain the battery.
No, there is no standby drain on the Klarus lights, because they use a tailcap clicky switch. Standby drains are only needed in electronic devices that need to be receiving power at all times to respond to an electronic command. The Klarus mode switch only works when there is power to to the device, controlled by the clicky.

Also in your low mode Duracell alkaline runtime graph in this thread and the Xeno E03 thread, the Klarus is stated as 2 hrs. 49 minutes. Should that read 20 hrs. 49 minutes?
Thanks, that is a typo - I'll correct it next time I have the data files open.
 

pascual

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But another quibble – I can understand dispensing with the Fenix-like Med on the other models in the Klarus line, but on the ST10 (like the LD10) this means you will see little difference between its two highest output levels. I don't know what the 2xAA Klarus is like (maybe it uses the same head as the ST10, like the Fenix LD20/LD10?), but I would have liked to seen levels spaced differently on the 1xAA version. :shrug:



Selfbuilt - so how would you like to have seen the modes/lumens spaced? The two highest output, 60 and 140, you are saying there is little difference between these two outputs?
 

selfbuilt

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Selfbuilt - so how would you like to have seen the modes/lumens spaced? The two highest output, 60 and 140, you are saying there is little difference between these two outputs?
Personally, I prefer the Fenix spacing (i.e. I like the Med mode), but I also like the extra moonlight on ther ST10. :shrug:

In this case, I find the ST10 Med mode is actually closer to ~100 estimated lumens (with ~160 for Hi, ~8 for Lo, and ~1 for Moonlight). That is a pretty big difference between Med and Lo.
 

pascual

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I see - just to clarify, (as you can see, I am new to all this based on my number of posts etc.), eventhough Klarus manufacturer says the Med mode should be 60, it is actually about 100 lm, making the jump from 100 med to 160 hi, not that big of a difference. HOWEVER, should the flashlight really produce what it says it should produce, 2 moonlight, 12 lo, 60 med, and 140 hi, you would like it. Is that correct?

Also, i have read all your acticles about definitions of relative light output,beam distance, etc. and I think get understand or get the gist of it - however, I am still confused about Peak Throw (lux@1m). For the ST10, it says the Peak Throw (lux@1m) is about 1800. based on your definition, I am still confused on what it means or how to interpret/use that information. Like is 1800 the lux/candela or can I convert it to lumens etc.?? sorry for the newbie question.
 

nikoncoolpics

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This is an amazingly detailed review. absolutley first class. I look forward to more like it.
 

selfbuilt

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For the ST10, it says the Peak Throw (lux@1m) is about 1800. based on your definition, I am still confused on what it means or how to interpret/use that information. Like is 1800 the lux/candela or can I convert it to lumens etc.?? sorry for the newbie question.[/SIZE][/FONT][/B]
The 1800 is indeed lux at 1m, which is the same as candela at 1m. Lux cannot be converted to lumens, as they are completely different (and independent). Lux is a measure of peak output at one point (the centre beam) and lumen is a measure of total overall output (captured in an integrating sphere). Lux is thus heavily dependent on the optics and focusing of the light, lumens should be independent of that.

In terms of throw, lux at 1m cannot be directly compared to other lights, since lux is a non-linear scale for distance (i.e. varies by an inverse-square law, for a point source of light). That is to say, a light that is moved to half the distance to the lightmeter will give you a lux reading that is four times higher. The only way to compare throw between lights is to normalize the data by taking a square root of the lux at a given distance. This is what ANSI FL-1 standard does as "beam distance", which is the distance (in meters) to when 0.25 lux would be measured. It allows you to directly compare the throw of different lights.

EDIT: Text edited to remove the output reference - I am referring just to the non-linearity of lux for distance.
 
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pascual

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Selfbuilt

Thank you for taking the time to answer this newbie question - what you said really helps make sense of the other articles I read that you wrote about this topic. You da man!!





The 1800 is indeed lux at 1m, which is the same as candela at 1m. Lux cannot be converted to lumens, as they are completely different (and independent). Lux is a measure of peak output at one point (the centre beam) and lumen is a measure of total overall output (captured in an integrating sphere). Lux is thus heavily dependent on the optics and focusing of the light, lumens should be independent of that.

In terms of throw, lux at 1m cannot be directly compared to other lights, since lux is a non-linear scale (i.e. varies by an inverse-square law). That is to say, a light that has an output mode that is twice as bright will give you a lux at 1m score that is four times higher. The only way to compare throw is to normalize the data by taking a square root of the lux at 1m. This is what ANSI FL-1 standard does as "beam distance", which is the distance (in meters) to when 0.25 lux would be measured. It allows you to directly compare the throw of different lights.
 

HKJ

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In terms of throw, lux at 1m cannot be directly compared to other lights, since lux is a non-linear scale (i.e. varies by an inverse-square law). That is to say, a light that has an output mode that is twice as bright will give you a lux at 1m score that is four times higher.

You have it backwards here, lux is the linear quantity, throw is the non-linear quantity. Double current in a led and you get (roughly) double power consumption, double lux, double lumen and 1.4 times the throw.
I.e. everything follows a linear relationship, except throw (The led conversion of current to brightness is not completely linear).
 
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