[selfbuilt]

Warning: pic heavy, as usual. :whistle:





Olight has updated their Baton S-series lights with a new model – the 1xAA S15. There are a number of build updates from the earlier S10 and S20 lights (although those models are also getting a facelift for 2013 – wait for my upcoming review of the new versions of those lights).

A nice feature of the new S15 is that it comes bundled with a 2xAA battery tube extender (and can even support 3xAA, with two extenders in place). Here's how it looks in 2xAA configuration:





From the way the light is marketed, you would be excused for thinking it is primarily a 1xAA light (with the option for extra cells). But based on my experience in this review, I tend to think of it as a 2xAA light that can be shortened … the reason for this distinction will become clearer as we go through all the testing results. :whistle:

Manufacturer Reported Specifications:
(note: as always, these are simply what the manufacturer provides – scroll down to see my actual testing results).

• LED: CREE XM-L2 LED and maximum output up to 280 lumens (tested by using 14500 rechargeable lithium battery).
• Output/Runtime: 280 lm (45min) / 70 lm (4hr) / 7lm (32hr) / 0.5lm (15d)
• Four adjustable brightness level: moonlight-low-middle-high and strobe; automatic memory function can memorize the brightness level while off (excluding strobe).
• With flashlight off, pressing side switch to directly activate high mode or moonlight mode.
• Beam Distance: 84m
• Beam Intensity: 1,750cd
• High efficient drive circuit, compatible with any rechargeable and non-rechargeable AA battery; The run time is up to 15 days under moonlight mode.
• Side switch with blue button cap, soft and comfortable to press.
• Aviation grade aluminum body, with anti-scratch type III hard anodizing.
• Stainless steel head ring can bear higher impaction.
• Special designed smooth reflector and 99% luminousness lens with anti-reflective coating on both sides make longer beam distance.
• With a long-arm convertible pocket clip for easy access.
• There is a lanyard hole in the tail which can pass through fabric strap with diameter of 2mm.
• With detachable strong magnet inside the tail, the flashlight can be attached vertically to any iron objects.
• Flat bottom allows stable tail standing.
• extremely low standby current: 0.5uA while using 1.5V battery; 1.2uA while using 4.2V battery.
• Battery reverse polarity function guards against improper battery installation.
• Lock-out function;
• Impact resistance: 2m
• Waterproof: IPX8
• Dimensions: 85mm/3.4" (L) * 23mm/0.9" (D)
• Weight: 46g/16.2 oz (without battery)
• MSRP: ~$50

The S15 comes in packaging that is very similar to the new Olight O'Pen (aka Foursevens Penlight). Inside the clear plastic container is the light, extra o-ring, a simple wrist lanyard, AA battery extender, and manual. There is also an overview of specs on the bottom and back of the packaging.




From left to right: Duracell NiMH AA; Olight S15; Zebralight SC52; Nitecore EA1; Foursevens Quark Mini AA; Nitecore MT1A; Sunwayman V11R with AA extender, Rofis ER12.




From left to right: Duracell NiMH AA; Olight S15; Nitecore EA2; Eagletac D25A2; Nitecore MT2A; Foursevens Quark Mini AA-2; Fenix LD20-R4; JetBeam BA20.

All dimensions directly measured, and given with no batteries installed:

Olight S15 1xAA: Weight: 46.4g, Length: 87.0mm, Width (bezel): 23.1mm
Nitecore MT1A: Weight: 54.6g, Length: 104.6mm, Width (bezel): 22.7mm
Nitecore SENS AA: Weight: 26.1g, Length: 82.7mm, Width (bezel): 19.8mm
Lumintop ED15: Weight: 59.7g, Length: 100.2, Width (bezel): 21.9mm
Zebralight SC52: Weight 39.5g, Length 79.0mm, Width (bezel): 22.6mm, Width (max) 25.4mm
Rofis ER12: Wright: 35.5g, Length: 96.2mm, Width (bezel): 18.6mm
Xeno E03:: Weight: 48.1g, Length 96.7mm, Width (bezel): 21.5mm

Olight S15 2xAA: Weight: 59.2g, Length: 137.9mm, Width (bezel): 23.1mm
Nitecore MT1: Weight: 66.9g, Length: 154.3mm, Width (bezel):22.7mm
Nitecore EA2: Weight: 68.9g, Length: 134.4, Width (bezel): 26.1mm
Eagletac D25A2: Weight: 54.8g, Length 148.5mm, Width (bezel): 21.0mm
4Sevens QAA-2 X (Tactical tailcap): Weight: 60.1g, Length: 149.1mm, Width (bezel) 22.0mm
Jetbeam BA20: Weight: 70.2g, Length: 156.4mm, Width (bezel) 23.2mm







As with the S10 and S20, the S15 is quite petite for its class. Overall build is similar to these earlier lights, with black anodizing (matte finish) and bright white labels. Although still without typical knurling, the S15 shares the same raised checkered pattern as on the S10/S20. With the pocket clip attached, I'd say grip is reasonably good.

The pocket clip is comparable to the earlier models, although longer than the original S10. It similarly seems to hold onto the light fairly securely. I personally like it, as you can clip it on you in either orientation (i.e., bezel-up or bezel-down carry), although it might be rough on clothing given how tightly it fits.

Like the S20 (but not the original S10), there is now a spring in the head. However, there is also a plastic disc surrounding it, which acts as reverse-polarity protection feature (i.e., flat-top cells won't work in the light).

Like the other Batons, the S15 uses square-cut screw threads (anodized for tail lock-out, like the S10/20).

Light can tailstand, and there is a split-ring/lanyard attachment hole on the side of the tail cap as before. The tailcap in fact seems identical to the S10/S20, with the same removable strong magnet (i.e., firm enough for the light to stand horizontally off any vertical metal surface). I previously prepared a video of the S10, showing you how to swap out the magnet in the tailcap:

Прямая ссылка на видео YouTube

They seem to have improved the design, as I no longer notice any rattle on the tailcap (as I did on the S10/S20 with the magnet installed). As before, the light uses an electronic switch, located near the head. However, the user interface has been updated from the earlier S10/S20 (see below). Also, the low-voltage warning LED that was present under the switch of S20 is gone now (i.e., there is no such indicator om the S15).

As before, the light has a flat stainless steel bezel ring with a red o-ring, and a relatively smooth reflector. One difference – the lens anti-glare coating is not as pronounced now. :thumbsup: This is actually good news, as I (and others) had found that the anti-glare on the S10/S20 lens was contributing to the relatively greenish tint.




The S15 has been updated with XM-L2 Cool White emitter (which was well centered on my sample). Note that the S10/S20 are also receiving updates for 2013, including the same emitter and user interface described below. The reflector of the S15 remains relatively smooth finish (like the older S10/S20 lights).

User Interface

The S15 interface has been updated from the previous S20. FYI, the new 2012 XM-L2 editions of the S10 and S20 will feature the new interface described below.

Like the other Baton lights, the S15 uses an electronic switch for on/off and mode control. As before, a quick press and release turns the light on.

Mode switching is controlled by holding down the electronic switch. The light will cycle between Lo – Med – Hi, in repeating sequence. This has changed from the earlier S10 models. As before, simply release the switch to select your desired mode. The light has mode memory – if you turn it off/on, the light returns to your previous level.

The S15 also features the ultra-low "Moonlight" level, as the S10/S20 did. You access this mode directly from off by a sustained (>1 sec) press-and-hold of the switch from off. This is a nice feature, as it means you can always turn the light on in the lowest possible mode if you want (i.e., no matter where you memorized it before). Mode cycling and memory works as before, once on.

Note that the S15 has a revised "soft lock-out" mode now - if you hold the switch down from off for >2 secs, the light shuts itself off (i.e., after one second of the Moonlight mode). You will not be able to use the light until you unlock it (by pressing-and-holding the switch for >2secs again). Note that this means that if you want Moonlight, you must release the switch before the lock-out takes effect (hold the switch between 1 and 2 secs).

There is still a "hidden" strobe mode, accessed by double-clicking the switch when on. Double-click again to return to constant on.

The low battery LED indicator below the switch is gone now, likely due to wider voltage support (i.e., the S15 supports 1xAA, 2xAA and 3xAA).

Video:

For information on the light, including the build and user interface, please see my video overview:

Прямая ссылка на видео YouTube

Video was recorded in 720p, but YouTube typically defaults to 360p. Once the video is running, you can click on the configuration settings icon and select the higher 480p to 720p options. You can also run full-screen.

As with all my videos, I recommend you have annotations turned on. I commonly update the commentary with additional information or clarifications before publicly releasing the video.

PWM/Strobe

As always, there is no sign of PWM at any output level – The S15 is current-controlled like its predecessors.



The strobe is a fairly typical fast "tactical" strobe, of 9.7Hz frequency (as before).

Standby Drain

As the switch is an electronic one, a standby current drain is always present when a battery is installed. However, it is so low that I was not able to get a stable reading with my DMM. When initially connecting, I got a brief ~1uA current, which then dropped down to a <1uA current. :ooo: At that level, it would take forever to drain a battery (roughly speaking). :laughing:

Beamshots:

For white-wall beamshots below, all lights are on Max output on an AW protected 18650 battery. Lights are 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.

1xAA Sanyo Eneloop NiMH













As you can tell above, the S15 is not driven as hard on 1x standard batteries as some of the competition.

1x14500 (AW Protected 14500) Li-ion













The S15 is certainly brighter on 1x14500, but again not at the top of this class range.

2xAA Sanyo Eneloop NiMH













Hi output on 2x sources is certainly more in keeping with other recent lights in this class, although the S15 remains relatively less throwy than most. Scroll down for detailed output and throw measures.

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

Throw/Output Summary Chart:

My summary tables are reported in a manner consistent with the ANSI FL-1 standard for flashlight testing. Please see http://www.flashlightreview... for a discussion, and a description of all the terms used in these tables. Effective July 2012, I have updated all my Peak Intensity/Beam Distance measures with a NIST-certified Extech EA31 lightmeter (orange highlights).






As you can probably tell from the above, there is remarkable consistency in the lower output modes, across all battery types. Where the light differs is in its response to different batteries on the Hi mode (scroll down for my lumen table). Throw is about what you would expect from a light this size.

To further explore the differences in max output across battery sources, here is my summary lumen estimates table:



Although I didn't include it in the table above, note that 1xL91 Lithium has a lower Hi mode of ~130 estimated lumens. 2xL91 is in the same range as the other 2x battery sources. 2xAlkaline is similarly no different from other 2x sources.

Note that the above is not a surprise to me – it all comes down to voltage, and the ability of the cells to provide stable power (for regulation) at a given level. 1xL91 is frequently lower in output, due to its lower voltage. 1x3.7V Li-ion 14500 is much higher voltage, therefore pretty much indistinguishable from 2x sources.

UPDATE AUGUST 14, 2014: I just received another S15, that I personally purchased from an online vendor. There is apparently some variation in output levels on Moonlight/Lo among these lights, as indicated below.



Please keep these results in mind, if you are purchasing the light with the intent of getting well-defined Lo levels.

It bears repeating again that my estimated lumen scale is just that - an estimate, based on a consistent calibration of my lightbox. But even though the absolute value correlation is unknown, the relative comparisons still hold. All I can really say is that one light is higher or lower than another, by a certain relative percentage. So please don't get hung up on the absolute values of the estimates, or on small relative percent changes.

Output/Runtime Graphs:

Let's start by comparing the runtimes in 1xAA and 2xAA configurations, on all supported batteries:




Ok, there is a lot if info to absorb up there. But there is one very surprising result – the S15 is considerably more efficient on 2xAA battery sources than 1xAA. :ooo:

Normally, 2xAA has slightly more than twice the output/runtime capacity of 1xAA. The reason it is not exactly twice has to do with how both the circuit and batteries deal with the differing discharge currents at different voltages. On lights that support both, you will generally see slightly more than twice the output/runtime capacity (often with much better regulation) on 2x sources vs. 1x.

In this case, it is hard to give an exact efficiency difference, as the S15 is also considerably brighter on Hi on 2xAA compared to 1xAA sources (and by how much varies considerably across batteries). But if you compare the Med mode alkaline runtime (which is a consistent brightness on both 1xAA and 2xAA), you will see that the S15 2xAA alkaline has up to ~3.5 times the output/runtime capacity of 1xAA alkaline. :bow:

Clearly, the S15 is optimized for 2xAA battery sources. The question is how does it compare to other 1xAA and 2xAA lights? In other words, is it a substandard 1xAA performer, a stellar 2xAA performer, or something in between?

Let's start with 1xAA:











Again, there's a lot of data up there, but one thing is clear – on 1xAA, the S15 is an excellent performer on its Med mode (relative to the competition), and a fair-to-mediocre performer on its Hi mode (i.e. closer to XP-G lights in output/runtime). The one exception is Hi on the higher voltage 1x14500, where it performs much better (as expected).

How about 2xAA comparisons?








On both Med and Hi, on 2xAA, the S15 is an outstanding performer.

Taken together, these results show that the S15 has an incredibly efficient circuit at all levels - except for standard batteries (NiMH, alkaline, or L91) on the Hi mode with 1x sources.

To summarize all that, the S15 is currently one of the top output/runtime efficiency performers in this class. It is just the Hi mode on standard batteries on 1xAA where you get performance comparable to a XP-G-based light. Note that the S15 is also generally speaking a better performer on NiMH, L91 or 14500, compared to standard alkalines.

If I can get my hands on another battery tube, I'll see how 3xAA compares. :wave:

UPDATE AUGUST 17, 2013: Here's a revised NiMH Hi mode runtime graph, showing 3xNiMH on my original S15, plus a 1xNiMH runtime on the new sample I purchased.



As you can see, there is a slight bump in output on the new sample. But what I find interesting is how the second extension tube on the first sample didn't really extend the runtime that much further past the 2xNiMH test. It really does seem like ~2.5-3V is the "sweet spot" for running this light (i.e., the outstanding performance of 2xAA).

Potential Issues

All Baton lights use an electronic switch, and therefore require a small stand-by current when fully connected. However, the standby drain on S15 was so low I couldn't even measure it accurately. This means you don't have to worry about draining your battery – although accidental activation is always a potential concern with electronic switches. You can "soft" lock out the switch electronically, and you can always physically lock out the S15 at the tailcap.

All my earlier S10 and S20 samples had a noticeably green tint overall, especially so at the lower output levels. Part of this was due to the anti-glare coating on the lens, and part was due to the natural warm tint-shift that occurs at low drive currents. I am happy to report the S15 has a reduced anti-glare coating, which improves the situation slightly. However, you are still likely to notice a green-yellow tint in the hotspot, and blue-purple tint around the edge of the spillbeam periphery – but it is less pronounced than the earlier S10/S20.

There appears to be considerable variation is the exact output levels of the Moonlight and Lo modes. As you will see in my revised result tables, a second S15 sample had only ~1/3 to 1/4 the output of my first sample, at these two levels.

Preliminary Observations

It is nice to see that Olight is continuing to update the build and user interface of the Baton series – as well as expand into the new battery configurations. The 1xAA/2xAA/3xAA S15 is a good addition to the family.

The build changes are generally all positive. The anti-glare coating on the lens has been reduced from the S10/S20, which should improve the green-tint-shifting known on this series. The slightly revised user interface is good, with a multi-second lock-out mode now. The clip has improved in length from the original S10. And the always low standby current has been reduced even further – it's so low, I can no longer get an accurate reading. :thumbsup:

The one thing people might miss is the low-voltage warning indicator LED under the switch, which is gone now. But I could see why that would not be feasible in this light, given the wide voltage support (i.e., 1x, 2x, and 3x AA are all supported).

The bundled 1xAA extension tube is nice touch, as you have the option to run the light in 1xAA or 2xAA configuration right out of the box (3xAA is possible with an additional extender). But as I mentioned in my introduction, this is one light that I see primarily as a 2xAA light (with the option to drop down to 1x).

The reason I say that is the output/runtime performance of the light – it is simply outstanding on 2xAA sources, at all levels. :bow: On 1xAA, there is a definite drop in efficiency on Hi (although Med still seems excellent in my testing). Basically, the Hi mode is a top-performer on 2xAA, and a middling-to-below-average performer on 1xAA (i.e., on Hi, you only get the output/runtime performance of a typical XP-G light on 1xAA). Again, the light performs extremely well on Med, in all configurations and battery sources.

One other thing to keep in mind is that the light also supports 1x14500 3.7V Li-ion, where you get the output level (and relative efficiency) of the 2xAA configuration. Oh, and if you aren't sold yet, you also get a top-of-class output level on 2xAA.

As with the S10/S20 Baton lights, expect a generally floody beam pattern – with a wide spillbeam and relative broad hotspot. Tint has improved slightly over my older Baton lights, but there is still a noticeable green-yellow-tint shift at lower levels.

The S15 is a nice example of the ongoing evolution of the Baton series of lights. Certainly a very strong contender in the slim and compact group of 1x/2x AA lights. :wave:

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S15 was supplied by Olight for review..

[andyz]

Well done, as usual.

Thanks for sharing with us.