Warning: pic heavy, as usual.
Welcome to my first review of the Viking series from ArmyTek. This series is very similar to the concurrent Predator models, only with XM-L2 emitters (for higher max output, and a less "throwy" beam). In this review, I will compare the Regular and Pro versions of the Vikings. Please see my companion review of the latest versions of the Predator models (v2.5 with XP-G2 emitters), published separately.
Manufacturer Reported Specifications:
Note: as always, these are simply what the manufacturer provides – scroll down to see my actual testing results. Specs have been highly condensed from ArmyTek website and manuals (and where inconsistencies arise, I have presented what is included in the printed manuals).
- LED: XM-L2 U2 Cool White
- Comfortable beam pattern
- Constant brightness for whole operation time
- Powered by one 18650 Li-Ion or two CR123A/R123 batteries
- Ultra-transparent and tempered glass with anti-reflective and lens coating, normally used in photo equipment only.
- Angle of the light spot: 10 degrees, angle of the light spill: 40 degrees.
- Removable stainless steel clip, functional and easy to use.
- The ability to use batteries with a flat contact.
- Tailcap lockout.
- Impact-resistant bezels - steel bezels are covered by titanium compounds with a hardness of 2000-3000HV.
- Body cover: matte, anodized. Hardness: 350-400HV. Resistant to scratches and impacts.
- Body material: aviation-grade aluminum T6061-T6.
- Water resistance standard: IPX-8 (the highest)
- Dimensions: Length: 6.1 in, Body diameter: 1 in, Head diameter: 1.56 in, Weight (without batteries): 5.82 oz
- Output levels and runtimes: 1010 lm (1h 40min), 200 lm (8h), 85 lm (20h), 8 lm (155h)
- Beam distance up to 300 meters
- Easy manipulation of modes
- New-generation electronic driver with STEP runtime technology.
- MSRP: ~$90
Viking Pro v2.5
- Output levels and runtimes: 850 lm (2h 40min), 200 lm (7h), 70 lm (20h), 6 lm (155h)
- Beam distance up to 250 meters
- Fully programmable settings
- Current stabilization types are entirely changeable through the user menu: full stabilization (FULL), simple semi-stabilization (SEMI), stepped stabilization (STEP).
- Electronic driver is placed in a special aluminum capsule and has been completely covered with a durable compound. This actually protects it from both the environment and from mechanical damage.
- Lowest Firefly mode of 0.1 lumens, working for 130 days with ONE 18650 Li-Ion battery.
- S-Tek™ driver constantly monitors the temperature of LED and the electronic circuit and will prevent the LED overheating in extreme environments.
- Supports batteries without protection board (PCB), for example: LiFePO4 or Li-Ion.
- The automemorization of the last used mode can be turned on or off.
- Has the ability to save the user's individual settings in the Custom preset.
- Has the ability to reset of all settings of the flashlight to those built-in by the manufacturer (Military or Outdoor presets) or to the user's saved preset (Custom).
- MSRP: ~$110
Packaging is common for both versions - a typical carboard box, with ArmyTek logos and graphic design on it. Inside, the light comes packaged between two pieces of packing plastic-styrofoam, with a good quality holster with closing flap, wrist lanyard, spare o-rings, tail switch boot replacement cover, manual and product insert/warranty card.
From left to right: AW Protected 18650; Armytek Predator Pro v2.5, Predator v2.5, Viking Pro v2.5, Viking v2.5, CR123A.
From left to right: AW Protected 18650; Armytek Viking Pro, Viking; Eagletac G25C2-II; Olight M22X; Nitecore SRT7.
All dimensions directly measured, and given with no batteries installed:
ArmyTek Viking V2.5: Weight: 159.8g, Length 153mm, Width (bezel): 39.5mm
ArmyTek Viking Pro V2.5: Weight: 161.9g, Length 152mm, Width (bezel): 39.5mm
[ArmyTek Predator V2.5: Weight: 161.8g, Length 155mm, Width (bezel): 39.5mm
ArmyTek Predator Pro v2.5: Weight: 161.0g, Length 155mm, Width (bezel): 39.5mm
ArmyTek Predator V1.0: Weight: 134.6g, Length 153.9mm, Width (bezel): 36.7mm
Nitecore SRT7: Weight: 172.4g, Length: 158mm, Width (bezel): 40.0m
Eagletac G25C2-II (stock): Weight 141.0g, Length: 150.6mm, Width: 39.6mm
Eagletac TX25C2: Weight 93.6g, Length: 120.4mm, Width (bezel): 31.6mm
Olight M22: Weight: 148.4g, Length: 144.8mm, Width: 41.2mm (bezel)
Overall dimensions are similar to the concurrent Predator versions, and are consistent for this class.
As always, ArmyTek build quality is very high, and the lights have a very robust feel. Physically, the models are distinguished primarily by their emitters (XP-G2 on the Predators, XM-L2 on the Vikings) and corresponding reflectors. The Pro versions differ from the regular versions in terms of circuit features and interface. All lights come with a choice of bezel/tail ring colors and crenelation styles.
The ArmyTek finish is fairly unique in my testing - the bodies of their lights have a very thick matte finish anodizing that feels almost molded (i.e., it is very "grippy"). According to ArmyTek, this coating is much thicker than most lights (i.e., harder anodizing). Although the light lacks knurling, grip is actually quite decent thanks to this unique finish. And there are some ridge detail elements to help further with grip.
Note the grippier finish may show dirt, hand oil, etc, more easily than traditional glossy knurling. There are also few anti-roll features, aside from some cut-outs in the bundled rubber grip ring.
Lettering is very bright and clear, and exceptionally legible. In additional to model information on the body tube and bezel, the voltage range and supported cells are printed right on the light.
Screw threads are thick square-cut (trapezoidal), and anodized at the tail region of the battery tube and in the tailcap (for lock-out).
The tailcap switch is a forward clicky in all lights, with good feel. The spring is thicker and longer than typical on these sorts of lights, with a flat connector piece (so as not to scratch your batteries). The lights cannot tailstand.
There is a small raised contact point in the head, so high capacity flat-top batteries can be used. All my 18650 cells fit in the lights – there is in fact quite a generous amount of cell length space.
The Viking doesn't use the same "throwy" reflector as the Predator series. Instead, they have optimized the Viking reflector to produce a broader hotspot (i.e., a 10 degree hotspot angle now, instead of 5). Armytek informs me that could have made the Viking reflector "throwier", but they opted to produce a clear differentiation from the Predator line. Note that both series have a 40 degree spill angle.
Both my samples in this series came with smooth reflectors, so some artifacts are possible (I noticed a few on the Vikings). Emitters were all well centered on my samples. There is an anti-glare coating on the lens, which gives the signature ArmyTek green tint. ArmyTek claims this is a higher quality anti-glare coating normally found on photographic equipment.
ArmyTek doesn't supply diffusers, but the Olight M22 diffuser fits fine on all bezel styles (as should most ~40mm diffuser covers).
User Interface (UI)
The bundled manuals are sufficient to explain the basic functioning of the lights. However, the current v2.5 Pro manual lacks a description of the programming interface. You will need this if you are going to take advantage of the full feature set.
Fortunately, you can still download a copy of the old Predator Pro v2.3 instructions. According to ArmyTek, the main difference is in the specified output levels (i.e., refer to your v2.5 manual for the correct ones). Also, the default battery is now the LiFePO4 18650, and FULL stabilization is turned on by default on both lines, for both Military and Outdoor (these terms are all explained below).
I will give some highlights of what to expect below, but you will need to download those earlier instructions to actually configure everything. Note that the Pro light is reasonably straight-forward to use once programmed, but has a sophisticated programming interface (somewhat akin to the HDS/Ra and older Novatac/LiteFlux lights).
In simple terms, either light is turned on/off by the forward tailcap clicky switch (press for momentary on, click for lock on).
For the regular version, turning the light on with the head tight against the body gives you Max output.
With the head loosened, you get the choice of three modes accessed in sequence by soft pressing or clicking the tail switch off/on: Middle > Lo > Lower Lo, in a repeating loop. Note that you need to pause ~1 sec between presses or clicks to advance the modes.
The light does have mode memory for the head-loosened state, and returns to the last mode you had it in (if you leave it off for a few seconds, or click off-on rapidly).
And that's it – no blinky modes on the regular version.
For the Pro version, output modes are arranged in what ArmyTek calls two "lines" (i.e. head tight for "First line", and head loosened for "Second line"). Within each of these head states/lines, there are multiple modes that you can switch between. Switching is controlled by twist cycles of the head relative to the body (i.e. loosen/tighten or tighten/loosen to advance modes within each "line").
How many modes per line, and what they are, are fully user-programmable. The light comes with two factory pre-set set states, called "Military" and "Outdoor", and you can also set your own saved custom one. Military comes set by default, but you can switch between them in the programming menus.
Military is set with Full regulation, with the First line (head tightened) having three modes, accessed in sequence: “850 lumens” > "6 lumens" > "200 lumens". Second line (head loosened) has two modes: Strobe 15 Hz, and Firefly “1.5 lumens”. Again, you switch between modes by tighten/loosen (second line) or loosen/tighten (first line) head twists in under 1 sec.
I don't have specific lumen settings for the Outdoor mode pre-set, as these aren't detailed in the simple manual that accompanies the light. Also, see my actual testing results later in this review to see how these lumen estimates actually measure up.
Features of the Pro Model
To start, you can change any of those pre-set output modes to one of three Firefly modes, or anywhere along a 1-100% continuously-variable ramp (with flashes at 25%, 50%, 75% and 100% output over a 40 sec timeframe). In addition to constant output modes, you can select SOS, Beacon or Strobe mode. Within Strobe, you can set the frequency from 1 Hz to 50 Hz (see below for my actual analysis).
You can change the number of pre-set modes in First line from anywhere from 1 to 10 modes, and Second line from 1 to 5 modes (default is 2-3, depending on whether Outdoor or Military defaults are chosen).
You can set the auto mode-memorization feature for each line independently (i.e. remember last mode for both lines, neither, or only one or the other).
You can specify the battery voltage being used (2xCR123A 3V batteries, 1x18650 3.7V Li-ion, 2xRCR 3.7V Li-ion, 1x18650 LifeP04 3.2V). Unprotected batteries can also be used.
But what is truly innovative is the ability to set three different regulation patterns for the light. FULL regulation is as you’d expect – perfectly flat regulation for as long as the battery can handle it, then an immediate drop to off (although in this case to an ultra-low output state, rather than off). SEMI regulation is what you typically find on a number of multi-power lights – the light maintains flat regulation for a while, then drops into direct-drive as the battery power dwindles. STEP regulation has is a similar overall efficiency to SEMI, but shows a step-down pattern of lowering outputs rather than a smooth drop-off. All of these patterns are shown in my runtimes graphs later in this review.
How to Program the Pro Model Settings
Again, you are going to have to download the old Predator Pro v2.3 instructions for the time being, if you want to be able to program the light. The manual explains what each of program selection options are.
But I can at least explain the general process. To select a variable output level in the first line, start from head tight and loosen the head for at least 1 sec and wait for the light to switch lines. Once it does, then immediate tighten, and wait again for the line to switch back. When it does, immediately turn off-on at the clicky. All the above has to be done in under 3 secs total, so timing is very tight (i.e. don’t delay on the head twist any longer than necessary to switch lines). It is highly unlikely that you would ever enter the programming state by accident.
Here is what the light will do, as plotted in estimated lumens (note: this is not my relative output scale, but actual computed lumens):
I show a blow-up insert of the first ~11 secs or, as the Firefly modes are too dim to compare to the continuously variable ramp.
As you can tell above, you get three Firefly modes in sequence, for about ~3 sec each with a ~1 sec off pause between them. This is followed by continuously-variable ramp from Lo to Max, which takes about 40 secs in total (with flashes at 25%, 50%, 75% and 100% output). Once Max output is reached, the light restarts at lowest Firefly and cycles through again. Make your selection by a loosen-tighten head switch.
The continuously-variable ramp is relatively visually-linear to the eye, and the quarter percent flashes are helpful to calibrate your relative setting. But you will have to be quick to select any of the truly low outputs. Note that the lowest non-Firefly level that I was able to capture off the contrinuous ramp was ~50 estimated lumens.
To enter the general programming menus, you start in the second line modes. Do the same as the first line output selection above, only starting with the head loosened (i.e. tighten, wait 1 sec, loosen, wait 1 sec, click off-on – all under 3 secs in total). Once inside the programming state, you double-click the tailcap to advance through menu levels, and tighten/loosen the head to select the menu entry you want. Menu levels and sub-levels are presented as a series of bright flashes. Please refer to the manual for a description of what each of the menus represent.
Again, the point here is that you will need the full instruction sheet to be able to re-program the light. You really can't do it without the proper manual in front of you. But once programmed the way you want, the light is straight-forward to use (as described at the top of this section).
For information on both the Predator and Viking series lights, including the build and user interface, please see my video overview:
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.
Light has no evidence of PWM on any mode, leading me to believe it is current-controlled.
UPDATE JULY 13, 2013: Actually, there is a reoccurring signal on the second Firefly mode (but not the first or third) of both the Viking Pro and Predator Pro. Unfortunately, the light intensity is too low for my oscilloscope sensor to detect, but I can measure the frequency by freeze-frame photography: it is 180 Hz on both lights. Without an oscilloscope trace to examine, I am unable to ascertain whether or not this is actual PWM. But regardless, this frequency of "flicker" is detectable by eye.
There is no strobe mode on the regular series model – it is only the Pro version that supports blinking modes.
The default strobe on the Pro is rated as 15 Hz:
Which, as you can see, seems pretty accurate according to my oscilloscope.
According to the full manual, you can set the strobe frequency anywhere from 1 to 50 Hz. Here's what I managed to set as the lowest and highest strobes:
And again, pretty good concordance with my oscilloscope.
Note that the original Predator claimed this same 1-50 Hz range as well – but the strobe frequency changed so quickly (i.e., at an accelerating rate) it was next to impossible to select the really high modes. I am happy to report the new Pro models provide a slower acceleration rate. You now have ~28 secs to select your strobe frequency, although you have less than ~8 secs to choose anything in the 20-50 Hz range. Still, this is much better than the original Predator, when you had ~1 sec to select anything in this range.
Here are some additional strobe modes that I captured, after ~6 secs and ~23 secs:
A minor point for you techno-geeks: as with the original Predator, the strobe pulse duration (duty cycle) does not stay entirely consistent across the full range of frequencies. A typical strobe mode has a 50:50 on/off cycle. But starting at the >30Hz frequencies on the Pro version, the on-pulse duration gradually increases to ~60% by the max 54 Hz (i.e., 60:40 cycle). That is more consistent than the original predator though, which was already at ~65% by 30Hz. None of this matters in terms of how disorienting the strobe is, but I thought I'd point it out.
As an aside, I don't find 54 Hz strobe very "disorienting" … it's almost like a really bad PWM rate at that level.
Beacon mode was 1 flash every 7.5 secs in my testing.
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 (but there may still be some variation).
Let's start with a comparison of the Predator and Predator Pro against the Viking and Viking Pro.
To show how you the Viking Pro compares against the competition, here are some comparisons to recent XM-L2 lights in my collection.
The new Viking v2.5 XM-L2 models from ArmyTek have a narrower spillbeam width than most other recent XM-L2 lights I've tested. Throw is pretty reasonable for the class, but it is not quite as high as some of the relatively throwy recent XM-L2 lights in this size class.
For outdoor beamshots, these are done in the style of my earlier 100-yard round-up review. Please see that thread for a discussion of the topography (i.e. the road dips in the distance, to better show you the corona in the mid-ground). FYI, any "streaks" you see across the images are bug-trails. Flying insects are often attracted to the bright lights, and their flight trails get captured as swirly streaks due to the long exposure time. Also, ignore any tint differences below – they are mainly due to the automatic white balance setting on the camera.
Again, let's start with a comparison of the Predator and Viking classes. For outdoor shots, I am only showing the Pro versions of the Predator and Viking.
ArmyTek intends for the Predator and Viking models to be used by different groups. As you can tell from the beamshots above, the beam patterns at a distance are clearly very different.
Now, let's see how the Viking Pro compares to some recent relatively throwy XM-L2 lights in my collection.
The Viking Pro is clearly not as throwy as some of the competition in this size class. ArmyTek has indeed succeeded in creating a more general purpose beam for the Viking model.
When I get the chance to do additional beamshots, I'll bring along the brighter regular Viking to compare, and update this review afterwards.
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.flashlightreviews.ca/FL1.htm 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 expected, The Predator models have less output – but more throw – than the Viking models.
Also as expected, the regular Viking had higher output than the Pro version (note the specs of "1010 LED lumens" for the Pro vs. "850 LED lumens" for the Regular version). FYI, "LED lumens" typically refer to theoretical max output of the emitter for a given drive level, and do not take into account actual losses due to the circuit, heat build-up in the emitter, reflector and lens effects, etc. All told, these can easily cut ~25-30% off the theoretical output levels. Note that ANSI FL-1 testing standard requires actual measurement of output "out the front", between 30-120 secs after activation. As such, my ANSI FL-1 lumen estimates of ~770 and ~670 (for Pro and Regular versions respectively) seem quite reasonable.
As you can tell from my direct beam measures, peak intensity throw is slightly less than some other XM-L2-equipped lights in this size class
How do my lumen estimates compare across the various levels?
As you can see, my results are fairly consistent across the board (taking into account my ANSI FL-1 estimated lumens vs ArmyTek's published "LED lumens").
Note: Unless otherwise stated, all my runtimes below are based on AW 2200mAh 18650 cells.
Ok, let's start with the base Regular model, on different types of cells.
The Regular model uses a "STEP" regulation method, where the light steps down in output by discrete levels, depending on the amount of battery power remaining. This is typically quite efficient (scroll down for comparison runtimes). What you can see above is that on Max, 2xRCR hits an abrupt termination (due to the protection circuits being triggered). But the 2xCR123A and 1x18650 show a very clear step-down pattern.
Let's compare that to the default "FULL" regulation method on the Pro version:
In FULL regulation, the light should abruptly shut-off on all Li-ion sources, without prior step-down. You can see that above quite clearly for the 1x18650 and 2xRCR runtimes. Interestingly, 2xCR123A continues to have a step-down pattern, even when FULL regulation is selected. One general comment here – you can expect a significantly shorter runtime on 1x18650 when FULL regulation is selected.
To demonstrate that, let's compare the various regulation patterns on the Pro model (STEP, SEMI and FULL – see UI section earlier in this review for an explanation of the terms):
As you can see above, SEMI and STEP have generally equivalent runtime – it just comes down to whether or not you like to see discrete steps. I am a bit surprised as how much lower the Max runtime was on FULL, but that may reflect the lower capacity 2200mAh cells used here (i.e., it's possible higher capacity cells may have handled the high drive level better). Personally, I recommend you program the Pro version to STEP or SEMI for maximum runtime (and clearer indication of battery life remaining).
Alright, let's see how the Regular and Pro versions do compared to the competition. To make the runtimes easier to distinguish, the Max modes on the Pro version were done in FULL and SEMI regulation (in contrast the typical STEP of the Regular versions).
Note also that I left the Pro version on FULL stabilization for the Med mode runtime. Based on my previous experience, there typically isn't much of a runtime difference between stabilization methods at the sub-maximal drive levels.
The performance of the Viking and Viking Pro are quite reasonable for the class.
Both Regular and Pro versions are easy to use in their default state. However (and as with all lights with complex programming modes), you will need to refer to the manual if you want to re-program any of the features or output levels of the Pro version.
The programming modes can be a bit tricky to navigate (i.e. requires multiple twists and clicks). You will need to make sure you keep the head threads clean.
The heavy thickness anodizing is interesting, and provides for reasonably good grip (i.e., I found these lights at least as good as most models with light-to-medium aggressiveness knurling). However, this finish shows up dust, dirt and fingerprint oils more easily than most lights.
The Viking models are somewhat less "throwy" than most other XM-L2 lights with similarly sized heads. This is intentional on ArmyTek's part, as the Vikings are designed to be general purpose lights. Those looking for more throw should check out my Predator series review.
Note that the spillbeam width is narrower on these lights than most of the competition. That said, most ~40mm size diffuser covers should fit and work on these lights (e.g., the Olight M22 diffuser works fine).
ArmyTek made quite a splash here with the launch of their inaugural light – the Predator V1.0 – over two years ago. The Vikings build on that original design and interface, but with a less "throwy" beam pattern.
As always, I find the ArmyTek build to be very robust – these are solid lights to handle. The trademark thick matte anodizing finish is very distinctive, and gives the lights surprisingly decent grip. The lens has a high-quality anti-glare coating, and the rubber grip rings and titanium-coated steel bezel rings and clip help to round out the package.
Of course, what has really distinguished ArmyTek lights are their sophisticated programming interfaces. In this latest iteration of the Viking series, they have opted for two steams – a Regular version (with a simplified clicky-controlled interface), and the Pro version (with the traditional programmable interface). Note that you don't need to actually program the Pro version to use it – it comes with a set of defaults (using a head-twist interface) that works easily, right out of the box.
But if you like to have a full range of control over the light, the Pro version's sophisticated interface lets you set as many pre-set levels as you like (anywhere from 2-15), with an extremely wide range of constant outputs and special modes available (e.g., three Firefly modes, strobe frequencies from 1 to 50+Hz, etc.). Probably the most unique feature of ArmyTek is the choice of three stabilization (regulation) patterns. Check out the UI and Runtimes section of the review for more information here.
I am glad to see that output/runtime performance is right on par with other decent current-controlled lights of this XM-L2 class.
In terms of beam pattern, the Viking models are a departure for ArmyTek. The Predator series is designed for max centre-beam throw (i.e., with their XP-G2 emitters and focused reflectors). The reflector used in the Viking models is specifically designed to produce a broader hotspot. This means that you may find the Vikings less "throwy" than a number of the competing XM-L2 lights in this size class. Please see the beamshots earlier in this review for more info. In any case, many of the ~40mm diffuser covers should work with the Vikings, giving you option of diffuse light if you want it.
ArmyTek is really trying to give you a clear choice between throw and a broad hotspot (i.e. Predators vs Vikings), and simple or sophisticated interface (i.e., Regular vs Pro versions). With the continual improvement updates to the Predator/Viking lines, there is little to criticize here – I like the subtle build and interface improvements that have been introduced since my original Predator V1.0 review.
I know this has been a rather long review, and there is common text to my companion Predator series review. Hopefully all this will help you decide if an ArmyTek light is right for you, and which model you should choose in that case.
Predator and Viking models provided by ArmyTek for review.