# Sunwayman V10A (1xAA, XP-G R5, Continuously-Variable) Review: RUNTIMES, BEAMSHOTS+



## selfbuilt (Feb 17, 2011)

*Warning: pic heavy, as usual. *







*Specifications:*

LED: CREE R5 LED (Cool White)
Digital Sensor Magnetic Control system, Infinite Variable Output Switch - slightly twist the Rotator Ring from left to right for Min to Max output.
Max: 140 Lumens
Min: 1 Lumen
Constant current circuit, constant output
Uses one single AA battery (Alkaline, Lithium, or Ni-MH) (Batteries not included)
High quality reflector maintains great throw distance and spread, as well as perfect beam pattern
Aerospace-grade aluminum alloy
Military Specification Type III- hard anodized body
Waterproof, in accordance with IPX-8 standard
Ultra-clear tough glass lens resists scratches and impacts
Tactical forward click switch for momentary on
Tail stand capable- can be used as a candle
Estimated MSRP ~$85
This is the first V-series Sunwayman light I have reviewed. Although the build looks very similar to the recent M-series light, the control ring now features a continuously-variable output selection feature (as opposed to the earlier defined levels and detents). 









Packaging hasn’t changed much. The light comes in a typical cardboard box with the usual extras - manual, warranty card, promotional insert, good quality wrist strap, pocket clip, extra o-rings and boot cover. 








From left to right: Duracell AA, Sunwayman V10A, Xeno E03, Fenix LD10-R4, 4Sevens Quark AA, Crelant 7G1, Zebralight SC51, Sunwayman L10A

*V10A:*: Weight: 58.1g (no battery), Length 100.6mm x Width 23.1mm (bezel)

The overall dimensions are pretty standard for a typical 1xAA light, if a bit on the tall side.




















Build of the V10A remains excellent overall. 

Although virtually indistinguishable from the recent M-series lights, the control ring is now smooth over the range (i.e. no detents, as no defined levels). Max range of the ring is unchanged at around 1/3 the total circumference of the light. 

The rest of build hasn’t changed. The light can still tailstand (with forward clicky switch). Square-cut screw threads remain anodized for lockout (but still only have a limited number of turns). 

The included pocket clip is serviceable, but these sorts of clip-on clips will never be as study or stable as ones that goes around the body tube.

Fit and finish is perfect on my sample, in the classic natural color common to Sunwayman lights. Lettering is bright white and clear. As before, there is no real knurling, so gripability is toward the low side (unless you have the clip attached).









Like the more recent M-series lights, the V10A comes with the Cree XP-G R5 Cool White. The reflector is what I would consider a light texturing/orange peel (LOP). 

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. 




























































As you can see, the beam profile of the V10A is in keeping with its class. Up close, I notice some faint rings in the beam, but these are not so great as to be disturbing (MOP may have helped here). 

Scroll down to my Summary Tables and runtimes for more specifics on output.

*User Interface*

Like with the M-series lights, you turn the light on by the tailcap switch. Half-press the tailcap for momentary-on, click for locked-on 

Mode switching is controlled by the magnetic control ring. The V10A features a continuously-variable interface – you control the output level by twisting the ring. You can select your desired mode while the light is off. 

And that's it - no blinking modes, no standby modes. 

*Ramping Pattern*

_EDIT: this section has been updated and revised from my initial post._

The big question is whether the output selection of the V10A is "visually linear". Generally, here on the forums, that has been taken to mean a logarithmic ramp as opposed to an actual linear ramp of outputs. The reason for this is that we perceive brightness in a non-linear way (actually, not just brightness - most of our sensory perceptions are non-linear). This is why twice the lumens doesn't appear twice as bright to us - lumens are an objective (linear) measure of output, and our subjective perceptions are not linear.

A logarithmic adjustment has long been used to adjust for our relative visual perceptions (e.g. the stops of camera are logarithmic). And like most here, up until now I have found that all continuously-variable lights with a logarithmic correction of output generally look "visually-linear". And then the V10 came along.  

To start, here is what the V10 looks like in my lightbox. To measure this, I slowly turned the ring at as close to a constant rate as I could manage, over ~25 secs or so. My lightbox collected output readings every second, and I then plotted the relative lightbox output against the estimated degree shift of the ring (i.e. with 360 degrees being a complete turn). Note the ring only turns about 1/3 the circumference of the light, or about 120 degrees.






I have blown-up the first third of the ramp in the inset graph, to show you that output does indeed increase over the whole ring (albeit seemingly slowly at first). Now, you can certainly argue that the output trace looks like it could be logarithmic. Indeed, if you plot it on a log scale, you get something approximating a straight line. However, the V10A does NOT subjectively appear to me to be visually-linear when handling (e.g. it does indeed spend a lot of time at the very low outputs over the first third of the ring).

Upon reviewing the scientific literature, I see that relative power relationships have superseded simple logarithmic corrections for linearizing our sensory perceptions. For perceived brightness, the currently accepted linearization method is actually a cube root of output. For a full discussion of this - including detailed graphs and primary literature references - please see my post #3 below.

When plotting with a cube root transformation of my lightbox's output scale, you get the following graph:






This graph MUCH better matches what I see by eye for the V10A, compared to a logarithmic plot. :thumbsup: I have added the LiteFlux LF5XT to the graph, as it does both a linear ramp and a logarithmic step pattern. Max output on the LF5XT on 14500 is also pretty close to the V10A on Eneloop, which facilitates comparisons. The linear and logarithmic ramps of the LF5XT also pretty closely match my relative perceptions. 

The point to the above is to show that the V10A goes to much lower outputs than any other linear or logarithmic continuously-variable light I've seen before. It also betters matches what I subjectively see across the whole range of outputs on these lights. So for now on, I will also include this type of plot (along with standard linear plots) for all the continuously-variable lights I review.

All that aside, I actually consider this dynamic range control of the V10A to be superior to a purely “visually-linear” ramp across the whole range. The logarithmic correction allows you to exquisitely fine-tune your low output selection. :thumbsup: And once you get into brighter outputs, the proportional increase seems quite linear.

*Current Draw*

You would hope that this wide range of low modes translates into a range of super-long runtimes. Unfortunately, the circuit overhead for this level of control is considerable, and Sunwayman estimates max runtime to be only 4 days.

I have measured the battery current draw at the lowest output as 50mA on 1xNiMH, which for a 2000mAh Eneloop would translate into 40 hours runtime. On 1x14500 (750mAh), I measure 13mA, which would translate into just under 58 hours. So, basically 1.5-2.5 days is all you can reasonably expect for most batteries :shrug:

*PWM*

I presume the light uses PWM for the variable outputs, but I was unable to detect the frequency with my setup (which means it must be in the high kHz range). It is certainly not detectable visually. :thumbsup:

At the highest output levels (i.e. over the last quarter turn of the ring), I was able to detect a weak signal in the near ~900Hz range on Eneloop and low 3kHz range on 14500. This seems to be some sort of circuit artifact – it definitely isn’t the PWM freq, as you could easily spot those levels with an oscillating fan.

*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.*











As you can see, the V10A’s max output and throw are very consistent for this class of emitter and light, on all batteries (i.e. it is much brighter on 14500). The lowest output mode is incredibly dim - I can barely measure it in my lightbox. Simply put, you can stare into the illuminated emitter quite comfortably at the lowest levels. :thumbsup:

*Output/Runtime Comparison:*































Note for the runs below that I set the control ring based on Eneloop output levels, so “~70%” and “~40%” don’t really apply to the 14500 runs. Rest assured, the light can go quite low on 14500 – almost as low as on standard batteries.










Overall efficiency seems reasonably good across the range of levels tested - especially considering the continuously-variable interface and (presumed high frequency) PWM-control. 

Of course, a current-controlled light with a limited number of defined (and optimized) output levels would be expected to outperform at comparable outputs. But the V10A seems at least consistent with typical defined-level PWM-based XP-G R5 lights.

*Potential Issues*

Some of the first batch of lights had an issue with flickering at lower output levels. These were recalled, and all currently shipping lights should be flicker-free.

Clip is basic, and may not adequately hold the light if sudden force is applied. Recommend you use a holster or the included wrist lanyard to secure the light.

Light body is fairly smooth (i.e. low in grip).

Relatively few screw threads hold the head onto the body.

Estimated runtime is not as great as you might expect on the ultra-low levels.

*Preliminary Observations*

I generally like the overall design and build of most of the Sunwayman lights, and the V10A is no exception. It shares most of the same design elements as the M10A and M10R, so it will seem very familiar to CPF users. The one exception is the control ring, which no longer has defined level detents, but is smooth across a continuously-variable range of outputs.

IMO, the dynamic range of the continuously-variable control ring is excellent on the V10A. While not consistently “visually-linear” in the classic sense, it is quite cleverly designed to allow you to access a wide range of low outputs, and then quickly access a roughly visually-linear set of high outputs. This is the first time I’ve seen this particular pattern, and it makes a lot of intuitive sense to me as I turn the ring (see the output ramp graph earlier in this review). 

The total traverse of the control ring is consistent with the earlier defined-level M-series lights, at around one third the total circumference of the light. Given the continuously-variable interface here, I would have preferred a bit of a wider range, but that’s a minor point.

I like the lack of detectable PWM with the V10A – rare on a continuously-variable light. :thumbsup: For this type of light, output/runtime efficiency seems quite good across the range of outputs directly measured. However, the overhead on the circuit seems fairly high, with an estimated lowest mode runtime of only 1.5-2.5 days, depending on battery source. :shrug:

I also really like the ability to use both standard batteries and 14500, with each battery type maintaining appropriate and reasonable output range control. Sunwayman has definitely gotten that right with the circuit - it provides a nice range of options for the end user. :twothumbs

To get a better feel for how the interface works in practice, I will be carrying this light around as my main EDC for the next little while. I will keep you posted on my experiences!

----

V10A supplied by Sunwayman for review.


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## selfbuilt (Mar 10, 2011)

HKJ 02-17-2011 07:44 AM said:


> As usual a good review, but you explanation of "visual linear" is flawed. The best way to see a visual linear ramp is to make the vertical scale logarithmic, then the brightness will follow a straight line in the chart.
> 
> My flashlight information page: lygte-info (only some of the contents is in English).
> English part with lots of outdoor beamshots and flashlight reviews: lygte-info English





Kackyl 02-17-2011 08:01 AM said:


> Your reviews rock as always. You've cost me more than anyone else around here has.
> 
> 
> 
> ...





srfreddy 02-17-2011 08:09 AM said:


> The v10r is what's been holding me back from the zebralight h51w. Excellent review, but visually linear=logarithmic.





selfbuilt 02-17-2011 08:33 AM said:


> Yes, that would be the way to _represent _a truly linear output ramp as "visually linear" in an output graph (since the eye sees things roughly logarithmically).But what I'm referring to here is not the representation of output ramps graphically, but rather the user's _relative perception_.
> 
> It is not easy to describe in text, since the terms get confusing (i.e. a truly linear ramp appears to us as logarithmic, and a properly-construed logarithmic ramp would appear to us as linear).Most lights tend to have a linear ramp, and thus do not look "visually-linear" to us in use (i.e. the first panel in my schematic).A few lights have a logarithmic ramp, which most people consider "visually-linear" when handling (i.e. the second panel in my schematic).
> 
> ...





selfbuilt 02-17-2011 09:36 AM said:


> I thought some actual data might help to clarify the point I was making above.Here is a graph comparing the V10A to a typical linear-ramp light (Jetbeam Jet-II IBS) and a "visually-linear" logarithmic light (Ray D1) with similar max output:
> 
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> 
> ...





HKJ 02-17-2011 09:44 AM said:


> The V10A looks closes to being visual linear, try plotting them with a logarithmic vertical scale with two decades.
> On a logarithmic scale 0.1-1, 1-10 and 10-100 would have the same size on the axis, 0 does not exist on a log scale.





selfbuilt 02-17-2011 01:33 PM said:


> Yes, plotting the V10A outputs on log scale would make it appear visually-linear _*on a graph*_.But that is NOT what users on the CPF mean by "visually-linear" - they mean it by their relative visual perception in actual use, not *log-transformed data* on a chart (which is what plotting on a log scale really means).
> 
> Part of the reason for the confusion here may be that I am using a crude lightbox to integrate the overall output.The lightbox relative output measures are a roughly good indicator of what the eye sees.If someone were simply using a lux lightmeter to measure center beam throw, then it would be appropriate to log-transform the data (since lux is non-linear scale, and light decays inversely with distance).
> 
> ...





HKJ 02-17-2011 01:54 PM said:


> For me visual linear follows a log scale. I have designed dimmers where I used the log scale and they where perfectly visual linear for me. In photo you also uses the log scale for exposure, one step is 1.4 times the brightness. RA light uses the same principle to make their adjustment visual linear.
> 
> This has nothing to do with "integrating the output", but you will have to apply you linearization before doing the log plot.
> 
> Logarithmic plots are often used, because it match our perception better. Try finding any plot of sound that uses a linear scale!





tbenedict 02-17-2011 02:00 PM said:


> Great review on an exciting light selfbuilt.
> 
> How does the twist action feel?Would it rotate in one's pocket without detents?
> 
> ...





Lobo 02-17-2011 03:27 PM said:


> Been looking forward to this review(noticed that you had runtimes on the V10A in your last review
> 
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> 
> ...





mhelskie 02-17-2011 06:19 PM said:


> such a great review! Hopefully, I'll have 1 before middle of next month ^_^





selfbuilt 02-17-2011 07:03 PM said:


> No argument with your first point - I agree with you.But in your dimmer example, if you were to measure the variable outputs of your log-dimmed light, would you then plot it all on a log scale as well (i.e. take the log of the log)?
> 
> That is what I am talking about here.If we take a light where the circuit designer has done the same thing - used a logarithmic scale for setting the outputs of a ramp to be visually-linear like your dimmer (e.g. Ray D1, Liteflux LF3XT, etc.) - and plot the outputs from my lightbox on a linear scale, we get a straight line (i.e. my Ray D1 graph in post #5).Taking the log of that gives you something that doesn't represent what you I see visually, and is not linear (i.e. the Ray D1 graph in post #7).
> 
> ...





tbenedict 02-17-2011 08:14 PM said:


> I like the look of those larger holes in the tail too.I look like paracord would go through it without a split ring (less scratching).Gosh I wish I had deeper pockets.





Outdoorsman5 02-18-2011 07:40 AM said:


> Outstanding review selfbuilt.
> Question, can the control ring be turned with one hand, or is this a two-handed operation?





HKJ 02-18-2011 09:25 AM said:


> Plotting a logarithmic quantity in a logarithmic scale is not taking a log of a log, but showing a log in the best possible conditions. This is also very obvious in your curve, with the log scale you can plot all the points in a meaningful way, with a linear scale you have nearly half the points on the zero line.
> With the log scale it is also easy to see that this light has a very good brightness selection, except for the highest bit.
> 
> You box does not produce a logarithmic output, to get a truelogarithmic plot, you would have to convert your lightbox readings to lumens,before plotting them in a log chart.
> ...





selfbuilt 02-18-2011 11:46 AM said:


> > Originally Posted by *tbenedict*I like the look of those larger holes in the tail too.I look like paracord would go through it without a split ring (less scratching).Gosh I wish I had deeper pockets.
> 
> 
> Yes, they are quite large (but there is also only so much room around the tailswitch cover).They are also arranged exactly at 90 degree increments (would be better to have a couple closer together for a lanyard).
> ...





gunga 02-18-2011 12:23 PM said:


> Great review.I have a few variable lights coming next week.Can't wait to try these out.I just wish they were easier to mod...





selfbuilt 02-18-2011 01:27 PM said:


> Yeah, a neutral white XP-G R4/R5 would look nice in there.





kaichu dento 02-19-2011 06:11 AM said:


> Make one in warm or neutral and I'll be all over it!





shigeu 02-19-2011 01:34 PM said:


> Selfbuilt, thank you for another great review. I am a big fan of Sunwayman lights and own several. I just wish that they had better clips. I do think that I will pick up a V10A for my boss (missus).





tbenedict 02-19-2011 04:15 PM said:


> I agree kaichu, I would be begging a pleaing with the wife if that was available.Really like how the interface sounds, the forward clicky with tailstand capability, and the ability to control the brightness before it is turned on.I looks like it might fit the hand well where some AA's are a hair short, which is fine for me since I don't typically carry a AA light in a front pocket.I guess it would have been a good alternative to a roll of quarters in my single days....






IMSabbel 02-20-2011 12:04 PM said:


> Thanks for the review. Ordered a CR123 one.
> 
> If its as good as it looks like, i guess a Ti AA one will join it...






okwchin 02-21-2011 10:57 AM said:


> I strongly feel that the V10R/A is Absolutely what I call visually linear. A turn of X degrees at the low end and the high end gives me the same proportional increase in brightness. To me THIS is truly visually linear. The D10 is NOT visually linear, for example, Far from it IMO.This is my opinion, and im happy to read it this way haha.
> 
> I also prefer the short movement of the ring, its almost on the "too much" side for me, because I can almost go from dim to bright single handed, without having to re-grip or use 2 hands. At the same time, there is more than enough control sensitivity to accurately dial a brightness, so I dont feel that it needs to be widened.
> 
> ...





selfbuilt 02-21-2011 01:32 PM said:


> > Originally Posted by *okwchin*
> > How do you find the ring movement vs brightness. Mine has the lower 2/3 of movement changing brightness, however it reaches full brightness at 2/3 turn, and there is no change in brightness for the last 1/3 of movement of the ring. There is also noticable flicker on any level other than full, at about 10hz or so.
> 
> 
> ...





IMSabbel 02-22-2011 01:51 PM said:


> Ok, my V10R arrived today.
> Damn, this is a nice light.
> 
> The ring is smooth enough to turn with one finger, and neither it nor the threads show any kind of grit to it.
> ...


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## selfbuilt (Mar 10, 2011)

_Originally posted by *selfbuilt* as post #28 on 02-25-2011:_

I’ve been going through the data for all the continuously-variable lights in my collection (including so-called logarithmic/“visually-linear” ones), and I think I can revise my earlier position on the V10A (and NiteCore IFE2, which shares the same circuit). I have also decided on a better way to graphically depict the difference, based on the currently accepted model of human perceived brightness.

To explain my original conundrum, here is a direct comparison of the V10A to a light that does both a linear ramp and logarithmic step pattern, the LiteFlux LF5XT. Max output on the LF5XT on 14500 is pretty close to the V10A on Eneloop (i.e. facilitates comparisons). Below is a graph where the y-axis is common (relative output), and the x-axis has been adjusted to show the dynamic range of each ramp (i.e. scaled to put everything in direct context for comparison). 






Although not all so-called “visually-linear” ramps exactly match the LF5XT logarithmic steps, I tend to trust that LiteFlux does indeed have a proper logarithmic-adjustment to the outputs. The V10A/IFE2 ramp seemingly looks quite different.

But it occurs to me now that this is not the best way to present the data, as the dynamic range of all the other continuously-variable lights is too narrow (i.e. they don’t go anywhere near as low as the V10A/IFE2). A better way to plot the difference would be to compare the ramps matched for output levels, like so:






At this resolution, it becomes clear the LF5XT’s logarithmic steps correlate very well with the V10A, for the range where the outputs are comparable. So would the LF5XT (and other lights with logarithmic ramps) also look the same as the V10A if they driven to lower outputs? They may very well. So far, on the basis of this comparison, I think you could be justified in calling the V10A logarithmic after all – it is just that that it has a much wider range of low outputs not previously seen.

The question is, are the V10A outputs “visually-linear” over the whole range? Clearly, the V10A is not linear in the linear plot of my lightbox's output readings. So should the lightbox outputs be plotted differently - like on a log scale, as some have suggested? Here's what happens if you do:






Well, that certainly looks pretty linear for the V10A. *The problem is, that is NOT how the V10A subjectively appears to me when handling.* :shakehead The linear plot is more correct in that the overall output doesn't change much over the first third of the dial. Also, the log plot is not accurate as to how the light seems over the last third of the dial either (i.e. the perceived output increases quite a bit toward the end, but the log graph is flat). Plus, the log plot doesn't represent how a traditional linear ramp looks either (i.e. it makes the regular LF5XT ramp seem like the output barely changes over the vast majority of the time ramp). 

So what's the problem here - how come the log scale doesn't accurately represent the perceived brightness over the full dynamic range of these lights? :thinking: Note that the presumption here has always been that logarithmic = “visually-linear”. But up until now, we only had examples with a relatively narrow dynamic range (i.e. the V10A goes much lower than other lights with a logarithmic ramp). Does this relative relationship still apply over this much wider range?

I know it sounds like heresy - but could logarithmic not be "visually-linear" over this wider range? :duck:

Before you all hit the roof, I’ve looked into the scientific literature on visual perception and perceived brightness (that is, the relative perception of varying light output), and found an interesting story. Although generally agreed that perceived brightness is non-linear, the method for “linearizing” it falls into two camps:

1. The Weber-Fechner Law calculates perceived brightness as a logarithmic function. This long-standing method dates back to the late 19th century, and seems to be the prevalent view here on the forums. It also seems to still be popular with amateur astronomers (for low-light viewing of stars through telescopes), and of course many shutter bugs are familiar with it as the basis for photographic light stops. The problem is that while it serves as a good general guideline, it is known to yield wide margins of error across different levels of light output (the limitations of the method are also long-standing - see for example the 1924 paper (ref #4) in my reference list at the end of this post). The general view in the perception field seems to be that a logarithmic-based Weber-Fechner conversion has been superseded by the Stevens' Power Law.

2. The Stevens' Power Law is a revision of the general Weber-Fechner law based on actual measurements over a much wider range of sensations (including vision). It calculates perceived brightness as a power function, with a specific power exponent derived for different types of stimuli. Although this method is relatively newer than the Weber-Fechner Law (i.e. first published in the late 1950s), it has been refined over the years under a variety of conditions, and is now the accepted method for calculating linear brightness more accurately. It is widely used for calibrating modern display devices (such as computer monitors and TVs), as well everything that plays on them (i.e. computer graphics, games, 3D modeling, etc.). The wiki link above shows you the measured power exponents for perceived brightness of different light stimuli (e.g. point source, etc.). For our purposes, the relevant comparison for the output of a flashlight beam is the perceived brightness of a "5-degree target in the dark" (i.e., with a uniformly dark background), which is calculated as the cube root of the total light output (i.e. power exponent of 0.33 in the wiki table). FYI, this stimuli choice and power exponent is also the basis for modern computer color brightness scaling.

Also, I should note that Stevens (and others who followed) were not the first to observe a cube root relationship for perceived brightness - I found one reference going back to 1927. Most of the modern literature reports a Stevens exponent for perceived brightness somewhere between 0.25-0.35, with 0.33 (i.e. cube root) the most common. See reference #1 below for a good summary and references. 

So let's see how the lights above look when transformed to a cube root output scale.






Now, that is a lot better, IMO. No, the V10A ramp is not "linear" on the graph, but it much better represents what I see when handling the V10A. It is also a lot better for depicting the relative perception of the LF5XT ramps. :twothumbs

I realize many may not like the implication of the last 50+ years of reserch that a cube root power relationship (i.e. Stevens' Power Law) is more linear for perceived brightness that logarithmic (i.e. the older Weber-Fechner Law). But that is what the literature suggests, and fits with my relative perception of all these ramping lights. Don't shoot the messenger! :shrug: 

For those interested, here are some some links to full-text academic research on the subject:


Does Stevens's power law for brightness extend to perceptual brightness averaging? Ben Bauer. The Psychological Record. 2009, Spring. 
Perceiving the Intensity of Light. Dale Purves, S. Mark Williams, Surajit Nundy, and R. Beau Lotto. Psychological Review. 2004, Vol. 111, No. 1, 142–158
A probabilistic explanation of brightness scaling. Surajit Nundy and Dale Purves. PNAS. 2002, Vol 29, No. 22, 14482–14487.
The Visual Discrimination of Intensity and the Weber-Fechner Law. Selig Hecht. The Journal of General Physiology. 1924
You can also find a general discussion in the online textbook Sensation and perception by E. Bruce Goldstein, 2007.

In any case, I am just trying to find the best way to graphically compare the difference between light ramps. I think the cube root scale better resolves the relative perceived difference between ramping patterns, and I will be including it along with linear plots in this and future reviews of ramping lights.

The key point remains – the V10A/IFE2 look very different from other continuously-variable lights, because of their ability to ramp to ultra-low outputs not previously seen.


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## selfbuilt (Mar 10, 2011)

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!).

My detailed discussion of the logarithmic vs cube root nature of perceived brightness (originally post #28) has been restored as post #3 above.

Please carry on!


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## tbenedict (Mar 11, 2011)

Any chance you are going to test the 2AA V20A? Also I noticed the specs on most of the listings indicate this light only goes down to 1 lumen.


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## selfbuilt (Mar 12, 2011)

No word from Sunwayman yet on other V-series lights. :shrug:

As for the low lumen estimate, it is clear that Sunwayman is considerably over-estimating it on my sample. The V10A produces one of the lowest outputs I've ever seen.


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## tbenedict (Mar 12, 2011)

I hope they adjust their specs for their own benefit. They could even add a blurb about the ramping curve.

After playing with a few ramping lights like the D10/D20 for a while, I can really see the low low and the ability to fine tune the low as a real selling point. Most lights jump out of the low area too quick, especially when you are already low and just looking for a little more or less.


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## samm (Mar 13, 2011)

Another great review, thank you. I love this light. I have the V10R also. It's so nice to have from one lumen up with a simple twist. You can always adjust it for* exactly* what your needs are, that blows me away.


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## selfbuilt (Mar 13, 2011)

Just an update - I have been EDCing this light for the last couple of weeks, and still really enjoy it. The only thing I would like is more grip to the ring (and greater visual distinction to the rest of the light).

FYI, check out my Nitecore IFE1 review if you are in the market for an 18650-version of this sort of light. The ramp is comparable, and the ring is easier to access.


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## IMSabbel (Mar 24, 2011)

I bought both the nitecore IFE2 and the V10R.

I like the sunwayman better.

Pros of the Nightcore compared to Sunwayman:
- Lower low
- Higher High (noticeable)
- Better grip on the ring

Cons of the Nightcore:
- SOS is NOT hidden in any way. I will inadvertably activate it any time I use the light more than a few minutes...
- The clip is an astrocity
- Stobe at the low-end of the wheel
- Does not Tailstand (switch rubber is a bit too big)


Some more comments to the control wheel: The one of the sunwayman is more intuitive. All the way right= bright, all the way left= dim, with nice logarithmic ramping in between. The turn range is short enough that you can ramp is all the way with a single twist, and the turn action is smooth as hell, so its no drawback in accuracy.

With the Nightcore, you have to different ramping speed regions (i assume that they use a combination of current and PWM modulation, as 5 orders of magntiude range would require 10MHz+ PWM frequency for a single stage light). It stays LOOONG in the <0.1 lumen range, and then picks up very quickly. The turning range is too far... you need 2-3 turn actions to get all the way to high brightness, the sunwayman is way sexier. 

Plus the stop... complete left is strope on the nightcore, and there is a "stop" between, where the light is off. I dont like it. It creates ambiguity ("light off, or on and in stop position?"), and to get to low-low, you have to manually adjust it _just_ before the stop. You cant just turn is to the end to get low light.

Also, the SOS mode activates whenever you go brighter-lower-brighter-lower, no matter how far each turn or at what brightness. As I like playing with the brightness, this is every few minutes.

So while technically the nightcore would be the better light (brighter and dimmer, 18650 cells, etc), the sunwayman is MUCH more fun to use for me in practice. Just a neat little light.


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## B0wz3r (Mar 25, 2011)

Selfbuilt, as usual, an outstanding review.

And, kudos on the perceptual science; I literally could not have done better myself, and I have PhD in perceptual and cognitive psychology (University of California, Santa Cruz, 2005). You presented all the relevant info clearly and concisely. The only thing I could have done differently would be to discuss some criticisms of Stevens' Law that address his use of the psychophysical reporting methods he developed, known as magnitude estimation. 

Recently, signal detection analysis methods have come to be applied to the study of these kinds of perceptual judgements, and while they have found some valid issues, they are just quibbles really, and it is a testament to Stevens' work that his principles hold up very well and work for 90% of all psychophysical judgements, and only break down when you get to the very high and low ends of the psychophysical range.

Again, outstanding review, and simply the best "layman" (I say that without knowing your qualifications, so I apologize in advance for my assumption) science I've ever seen. Adam and Jaime got nothin' on you!!!


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## selfbuilt (Mar 25, 2011)

B0wz3r said:


> And, kudos on the perceptual science; I literally could not have done better myself, and I have PhD in perceptual and cognitive psychology (University of California, Santa Cruz, 2005). You presented all the relevant info clearly and concisely. The only thing I could have done differently would be to discuss some criticisms of Stevens' Law that address his use of the psychophysical reporting methods he developed, known as magnitude estimation.


Thanks for compliment.  As with all my reviews, I try to be balanced and fair in my discussion of things - and the borader issues of perceived brigthness deserved similar treatment. It is definitely not my field (and it has been a long time since undergrad psych class), but I enjoyed looking into it. Of course, physics and electronics are certainly not my bag either, yet I review flashlights.  My actual background is basic biomedical research.

Not being my field, I tried to be as fair as I could to the logarithmic Weber-Fechner crowd. But it does seem clear, based on all the modern literature, that Stevens' power law is a better fit for most perceptual issues. I did notice the pyschophysical reporting issue when researching Stevens' law, and it does raise some flags for me. I do have some stats training, so I am immediately suspicious when the data better fits averaging of multiple respondents than it does actual individual ones. Reminds me a little too much of Asimov's "psychohistory" in the Foundation novels  (i.e. sounded good in the 1950s, when there was much more limited understanding of these things).

That being said, the wealth of literature since Stevens' time (and the reasonable range of exponents for non-point light sources that seem to be consistently found) suggests something around a cube-root is the best approximation we have.

Back on the topic for the V10A,  I find after EDCing it for awhile that the control ring is growing on me. Grip could still be better, but the range of motion and its fluidity work well in practice. While I initially prefered the NiteCore IFE2's longer ring traverse, I've grown more comfortable with the V10A. And I agree with the IMSabbel that the IFE2's SOS mode is too easy to activate accidentally - I will update that review.


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## tbenedict (Apr 5, 2011)

I'm guessing it has to, but does the control ring work when the light is off...and is there any preflash? I could see being able to rotate the ring to the far stop to be sure it comes on real low.

You can tell I really want one of these suckers (or the V20A).


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## IMSabbel (Apr 5, 2011)

Dont quite understand the first part of your question... the light output is depending on the ring position. Of course, it will do nothing when the light is off. But the absolute position is important, so when you turn it down while off it will turn on on low.

I did not notice any kind of preflash on mine, even when extensively using the forwards clicky at light with the light on total low.


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## selfbuilt (Apr 5, 2011)

tbenedict said:


> I'm guessing it has to, but does the control ring work when the light is off...and is there any preflash? I could see being able to rotate the ring to the far stop to be sure it comes on real low.


Yes, as IMSabbel points out, the control ring "works" while the light is off - that is, if you turn to a specific position, it will come on at the corresponding relative output level when you click the switch. This way, you can roughly set the output level of the light before turning it on (I say roughly because there are no detents - so aside from Min and Max, you will be making a relative estimate of output before turning it on).

And I also see no pre-flash. I have been using mine a lot over the last month or so, with no signs of it.


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## tbenedict (Apr 6, 2011)

Sweet, thanks!


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## AaronG (Apr 9, 2011)

selfbuilt said:


> Yes, as IMSabbel points out, the control ring "works" while the light is off - that is, if you turn to a specific position, it will come on at the corresponding relative output level when you click the switch. This way, you can roughly set the output level of the light before turning it on (I say roughly because there are no detents - so aside from Min and Max, you will be making a relative estimate of output before turning it on).
> 
> And I also see no pre-flash. I have been using mine a lot over the last month or so, with no signs of it.



I was interested in this too. I think I'm going to get a V10R Ti with AA extender tube. As long as the extender isn't too pricey.


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## swrdply400mrelay (Apr 13, 2011)

Thanks for the review!

Is it easy to take apart the head if you wanted to do a neutral emitter swap?

Thanks!


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## RBWNY (Apr 16, 2011)

Good review as always! I just ordered one of these today. I hope it can blow away the Quark - AA. I already use a 14500 in the Quark, and from the graphs you posted, it appears I might get a boost with the V10A by using one as well.


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## copfish (Apr 20, 2011)

Nice review. I'm looking for a single AA light to use on the boat and this looks like the ticket. The fact that you can adjust the output with one hand sells me on this light.


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## Animalmother (Apr 26, 2011)

How is the throw on this?


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## selfbuilt (Apr 26, 2011)

Animalmother said:


> How is the throw on this?


Throw and beam distance measures are given in the summary tables in the review. As you will see, the V10A does well in comparison to most lights of this class, but I wouldn't consider any regular 1xAA light "throwy", as such.


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## RBWNY (Apr 26, 2011)

Animalmother said:


> How is the throw on this?


 
I like it. Mainly because I'm using a 14500 which gives it a nice lumen bump. As a comparison, I also have a NiteCore IFE2 (2x CR123/1x 18650) and in outdoor situations I can't see any measurable difference in the two of them. Max brightness and throw are neck `n neck equal :thumbsup:

V10A's center hotspot is tighter with a slight brownish tint. More characteristic of other AA's I've seen.


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## Animalmother (Apr 27, 2011)

Ok thanks guys. I have a LD10 R5 I am thinking maybe I should have gotten the R4 version now.


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## tbenedict (May 14, 2011)

Well, I finally broke down and got one of these. I am really digging this thing.

I did notice that on all levels except wide open, it has a slight ramp when turning on. Kind of like the Proton Pro, but quicker. Seems neat when on the real low settings to prevent shock. I'm guessing the circuit has to load up a little and maybe hi has a different path in the circuit.

The only suggestions for improvement that I can see are:
1) Adjust the clicky so it is easier to click on with a thumb in the overhand grip.
2) Add a small notch so a lanyard won't affect tailstanding. I do like the larger holes.
3) Neutral tints (white on mine is good, just my general preference).


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## EngrPaul (May 20, 2011)

The lowest setting seems to vary from sample to sample. Probably due to variations in drivers.


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## Lou Minescence (Jul 24, 2011)

I didn't see any mention about a low battery warning during the review. My light flashes three times to warn of a low battery. It will draw my IMR 14500 down to 2.2 volts before flashing begins.


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## selfbuilt (Jul 25, 2011)

Lou Minescence said:


> I didn't see any mention about a low battery warning during the review. My light flashes three times to warn of a low battery. It will draw my IMR 14500 down to 2.2 volts before flashing begins.


Interesting, I had noticed that on standard cells in my original sample (but don't have IMR 14500 to test - always used protected 14500s). Could be a new feature.

FYI, one thing I did ntotice on my sample is the light flickers (think high-frequency strobe) on alkalines just before the cell is fully exhausted (i.e. well below 1% original output). This strobe effect stops if you dial down the output to a lower level (at least for awhile). Not sure if it happens on other cells - I stop NiMH long before then (bad for the batteries to let them drain that far), and use only protected Li-ions.


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## RBWNY (Jul 28, 2011)

Lou Minescence said:


> I didn't see any mention about a low battery warning during the review. My light flashes three times to warn of a low battery. It will draw my IMR 14500 down to 2.2 volts before flashing begins.


 
No flickering/flashing on mine. Have always used protected 14500's. Was using it yesterday when it just "went to black". Had Trustfire (flame) cell in it. Voltage around 2.8


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## Budda (Jul 29, 2011)

I own a RRT-0 with infinite brightness system, which I believe has almost the same circuit of this light.
in both lights the biggest complain for me is the lack of efficiency of the driver at the lowest modes and in standby.
My trusted 47 123^2 with R2 runs at 0.3 OTF lumen for months, this lights runs on a lowest level for less than half week.
And the parasitic drain in standby mode is too high. it happens often to me that I leave the light in standby and forget to switch off... than the next day I need a new battery.


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## selfbuilt (Jul 29, 2011)

RBWNY said:


> No flickering/flashing on mine. Have always used protected 14500's. Was using it yesterday when it just "went to black". Had Trustfire (flame) cell in it. Voltage around 2.8


Yes, that's exactly what's expected with a protected cell. I don't have any unprotected 14500s to test, so I don't know if what Lou reports is a new feature, or was always present.



Budda said:


> I own a RRT-0 with infinite brightness system, which I believe has almost the same circuit of this light.
> in both lights the biggest complain for me is the lack of efficiency of the driver at the lowest modes and in standby.
> My trusted 47 123^2 with R2 runs at 0.3 OTF lumen for months, this lights runs on a lowest level for less than half week.
> And the parasitic drain in standby mode is too high. it happens often to me that I leave the light in standby and forget to switch off... than the next day I need a new battery.


Yes, the performance here is similar. Although the V10A doesn't have a standby mode, current drain at the lowest level suggests you would only get 1.5-2.5 days of runtime (max) off a fresh battery, depending on battery type.

In my testing of the Nitecore IFE2 (which also has a similar circuit), the standby mode is just slightly less than the lowest brightness level. Since the RRT-0 presumably has a comparable circuit, I'm not surprised by your result.


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## kahuna2793 (Aug 1, 2011)

How many lumens with 14500? and runtime.


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## selfbuilt (Aug 1, 2011)

kahuna2793 said:


> How many lumens with 14500? and runtime.


Ah, both of these pieces of info are in the review. :thinking: Check out the summary tables and runtime graphs.


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## kahuna2793 (Aug 1, 2011)

Sorry I don't understand what 50% ?
sunwayman V10a (XP-G R5 ) max=59 min to 50%

QUOTE=selfbuilt;3707562]Ah, both of these pieces of info are in the review. :thinking: Check out the summary tables and runtime graphs.[/QUOTE]


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## RBWNY (Aug 1, 2011)

kahuna2793 said:


> Sorry I don't understand what 50% ?
> sunwayman V10a (XP-G R5 ) max=59 min to 50%
> 
> QUOTE=selfbuilt;3707562]Ah, both of these pieces of info are in the review. :thinking: Check out the summary tables and runtime graphs.


[/QUOTE]

59 min to 50% refers roughly to the amount of time you can expect the light to run on max brightness, before it downshifts to 50% of its highest lumens. Personally I don't think it matters that much when using rechargeable cells. :naughty:


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## RBWNY (Aug 1, 2011)

As a quick aside to my last post.... the only thing I don't like about using 14500's in this light, is how HOT it gets on high! (very quickly too)


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## kahuna2793 (Aug 1, 2011)

Thanks for the info. What battery best overall



RBWNY said:


> As a quick aside to my last post.... the only thing I don't like about using 14500's in this light, is how HOT it gets on high! (very quickly too)


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## RBWNY (Aug 1, 2011)

kahuna2793 said:


> Thanks for the info. What battery best overall


 
I have 2 types. AW and Trustfire (w/flame).


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## selfbuilt (Aug 1, 2011)

kahuna2793 said:


> Thanks for the info. What battery best overall


I strongly suggest you check out the "electronics - batteries included" forum here for info on batteries, or one HKJ's Li-ion reviews 

AW and Redilast are among the most popular brand names here.


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## OneBigDay (Aug 18, 2011)

Does the V10A officially support 14500? The sales references to this light that I have seen only say...



 Uses one single AA battery (Alkaline, Lithium, or Ni-MH) _ (Batteries not included)_
You would think if it could handle the higher input voltage they would advertise it as such? In my cynical brain it seemed they had gone out of their way to put a different circuit in here than in the V10R, but I couldn't figure out why they would do this. :shrug:


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## selfbuilt (Aug 18, 2011)

OneBigDay said:


> Does the V10A officially support 14500? The sales references to this light that I have seen only say...


Sunwayman confirmed my sample supported 14500, and I've been EDCing mine this way ever since, without incident. Don't know why they aren't more specific in the literature. :shrug:


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## OneBigDay (Aug 19, 2011)

Thanks for the reply. This is great news!

I also found this link, which is in german but if you send it through a translating service (or can read german) you can see that wherever this info came from the V10A is clearly marked to accept voltage up to 4.2 v. :thumbsup:


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## tbenedict (Sep 2, 2011)

Here is a pic of my V10A manual. Note the voltage range.


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## orbital (Sep 5, 2011)

+

hi selfbuilt,
if you have calipers, would it be possible to measure the *inside diameter* of the V10A battery tube.

I have a couple 17500s' with the labels off are 16.20mm wide,
... just wondering if they would fit.

thanks in advance~ :thumbsup:


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## selfbuilt (Sep 5, 2011)

orbital said:


> if you have calipers, would it be possible to measure the *inside diameter* of the V10A battery tube.
> I have a couple 17500s' with the labels off are 16.20mm wide,


No, fraid not - the internal diameter is only 14.6mm on my V10A. Plenty of room for the AW 14500 protecteds (~14.1-14.2mm at max diameter).


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## orbital (Sep 5, 2011)

selfbuilt said:


> No, fraid not - the internal diameter is only 14.6mm on my V10A. Plenty of room for the AW 14500 protecteds (~14.1-14.2mm at max diameter).



+

Thanks for taking a look at that 
& thanks for your great work.


_____


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## Mags (Sep 30, 2011)

Is there a reason that running on 14500 achieves less throw than an M10A on RCR123? I know it may be apples and oranges, but I read somewhere that the V10A and V10R have the same heads and current levels are pretty similar between the M and V series.


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## selfbuilt (Sep 30, 2011)

Mags said:


> Is there a reason that running on 14500 achieves less throw than an M10A on RCR123? I know it may be apples and oranges, but I read somewhere that the V10A and V10R have the same heads and current levels are pretty similar between the M and V series.


They should be pretty comparable, if the lights are driven the equivalent levels on max. But in my case, my M10R was the original batch with a XR-E R2-bin, which will throw further than modern XP-G emitters (even those with a higher output bin).


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## dajab77 (Nov 26, 2011)

Great review. After reading this I think I will put this light on my Christmas wish list. 
Thanks
Jab


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## xtestifyx (Nov 28, 2011)

Just to add to selfbuilt's already amazing review, here's some information "FYI"

The included Lanyard with my V10A T-6(XML) is actually not Paracord of any kind. The inside material is a Nylon braid


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## tobrien (Nov 28, 2011)

so does it make more sense to get _this_ R5 iteration or the new(er) XML version?


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## candle lamp (Dec 12, 2011)

Thanks for your excellent review as always. Selfbuilt! :thumbsup:

I have a V10A(XM-L version) and found that the light with an Eneloop flicker continuously when the battery voltage drop to a certain low level(don't know the voltage). 
Also the light with a 14500 li-ion just go out without any warning(indication) like an Eneloop when the cell voltage is about 3.0V.
I think those results are due to the low battery warning function. 

Did you see the same result as mine with 14500?


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## applevision (Dec 12, 2011)

Wow, I just stumbled upon this light and this wonderful *selfbuilt *review... I think I will need to pull trigger on this one... Outstanding!


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## selfbuilt (Dec 12, 2011)

tobrien said:


> so does it make more sense to get _this_ R5 iteration or the new(er) XML version?


The XM-L will be brighter on 1x14500 sources, but max output will likely be little changed on standard batts. Overall efficiency is also similar between the two emitters, except at the higher output levels on XM-L.

Throw will definitely be lower on the XM-L, compare the XP-G, for equivalent output levels.



candle lamp said:


> I have a V10A(XM-L version) and found that the light with an Eneloop flicker continuously when the battery voltage drop to a certain low level(don't know the voltage).
> Also the light with a 14500 li-ion just go out without any warning(indication) like an Eneloop when the cell voltage is about 3.0V.


Looking at my runtimes, it does seem like the my XP-G version may have flickered as the battery was nearly exhausted. But this is unlikely to be a low voltage warning - that would have been visible as a series of flashes much earlier in the run (which I do not recall seeing). It is not uncommon for a lot of lights to flicker as the battery is nearly dead - this seems to be a circuit issue as it tries to draw power from a nearly exhausted source.

As for cutting-out on protected 1x14500, that is perfectly normal - most well-regulated lights tend to do that on protected sources. It is only on direct-drive lights where you may have a long drop-off period before reaching the protection cut-off.


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## tobrien (Dec 12, 2011)

selfbuilt said:


> The XM-L will be brighter on 1x14500 sources, but max output will likely be little changed on standard batts. Overall efficiency is also similar between the two emitters, except at the higher output levels on XM-L.
> 
> Throw will definitely be lower on the XM-L, compare the XP-G, for equivalent output levels.


thanks buddy! 

I'll probably go for the XML then. Although I will say, my ZebraLight SC51 has a perfect flood/throw combination with its XP-G, but I don't know how deep or shallow the reflector is on this V10A you reviewed, any idea on how the two compare in their reflector depths? I may end up doing the XM-L version of the V10A if it has a deeper reflector so I get the same flood I suppose


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## naked2 (Dec 16, 2011)

A couple questions for anyone:

1. Anyone lose the "tint lottery" and receive an XP-G model with green :sick2: tint?
2. Although selfbuilt confirmed stock body won't fit 17500, has anyone bored you their's for 17500; or even 18500? I seem to remember reading somewhere that the V10R Ti w/ AA adapter could be bored for 18500; if that's possible, I don't see why it wouldn't be for this model also. I've searched here and CPFMP and couldn't find anything though.

Thanks in advance, Tony


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## NoFair (Dec 17, 2011)

My V10R is normal cool white, no green. The Anniversary edition has a perfectly neutral XM-L 

Both pull 2A from a IMR li-ion on max, so no wonder they are bright


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## naked2 (Dec 17, 2011)

*Re: Sunwayman V10A (1xAA, XP-G R5, Continuously-Variable); can it be bored?*

Thanks; good to hear your XP-G isn't green! I've since ordered a V10A XP-G, and hope I can have it bored for 17500 or even 18500.


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## NoFair (Dec 17, 2011)

Don't think 18500 is doable, but a 17500 might work fine. Need to remove the switch etc. and see if you can find a machinist who will do it for you.


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## naked2 (Dec 17, 2011)

*Re: Sunwayman V10A (1xAA, XP-G R5, Continuously-Variable); can it be bored?*

The machinist is no problem; I was just hoping to hear from someone who has actually had it done.


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## NoFair (Dec 17, 2011)

*Re: Sunwayman V10A (1xAA, XP-G R5, Continuously-Variable); can it be bored?*

Someone has it seems (looks like 18500 is possible): http://www.candlepowerforums.com/vb/showthread.php?310520-Sunwayman-V10R-Ti-Clip-Options&p=3730238&viewfull=1#post3730238

Post #64


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## naked2 (Dec 17, 2011)

*Re: Sunwayman V10A (1xAA, XP-G R5, Continuously-Variable); can it be bored?*

Curious, what keyword/s did you enter to search? I couldn't come up with *anything* here or on CPFMP.


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## NoFair (Dec 17, 2011)

*Re: Sunwayman V10A (1xAA, XP-G R5, Continuously-Variable); can it be bored?*

17500 and V10a did the trick I think:devil:


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## naked2 (Dec 17, 2011)

*Re: Sunwayman V10A (1xAA, XP-G R5, Continuously-Variable); can it be bored?*

Thanks again!


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## Cunha (Dec 21, 2011)

*Re: Sunwayman V10A (1xAA, XP-G R5, Continuously-Variable); can it be bored?*

This is sort of a newbie question, but people have mentioned parasitic drain in "standby mode" what exactly does this mean? Will the batteries deplete when they are fully installed in the light and the light is switched off?


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## selfbuilt (Dec 21, 2011)

*Re: Sunwayman V10A (1xAA, XP-G R5, Continuously-Variable); can it be bored?*



Cunha said:


> This is sort of a newbie question, but people have mentioned parasitic drain in "standby mode" what exactly does this mean? Will the batteries deplete when they are fully installed in the light and the light is switched off?


That is what a parasitic drain means, but the V10A doesn't use a standby mode. It has a physical switch for on-off, so there is no drain. A drain is required on electronic switches, because the switch always needs to be drawing a small amount of power to be able to respond to a press.

On lights that have an electronic switch with parasitic drain, the rate of drain can be highly variable - anywhere from a few days to a few decades to drain the cells, depending on the current draw (i.e. how well the circuit is designed). And in most cases, you can break the drain by simply disconnecting the head from the body (so long as threads are anodized). But again, no worries with the V10A - there is no drain when off.


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