Category Archives: Flashlight Resources

My YouTube Channel – @cpfselfbuilt

One of the features I wasn’t planning to continue in these new reviews was my individual light video overviews on my YouTube channel: @cpfselfbuilt

Back in the day, I found these rather labour-intensive to plan out and produce (even with only minimal editing/processing). And the video format doesn’t allow you to easily update or correct information (except by cards or other pop-ups), which can be frustrating.

I also used them mainly to show the build and user interface – figuring it was often easier to explain visually than with a lot of text. But with these new 2023 reviews, I’m focusing on simplified point-by-point UI descriptions, to serve as manual replacements. So I figured the need for (time-consuming) videos was reduced now.

And to be honest, I also got tired of the constant complaints from many commentators on that site about the lack of outdoor beamshots in the videos. As I painfully tried to explain repeatedly, they have no real value for comparative testing if you are using an auto-brightness-adjusting cellphone camera (as I was for the videos) – everything would look misleadingly bright. And I was already providing fixed-camera-setting comparative beamshot pictures in my actual reviews – video recordings of the same would have no additional value. But it seems like outdoor beamshot videos was all a lot of YouTubers cared about, and the constant trolling on every new video was annoying.

But as I also had a lot of supportive subscribers on that channel back in the day, I figured I owed them a video introducing my return to reviewing. So I posted the video below, outlining my interest in the 21700 battery class in particular:

I must say, I’ve been a bit blown away by the immediate and overwhelmingly positive response to this announcement video!  I had figured that most people would have long-ago unsubscribed, and it was mainly bots that were left on the site. It seems I underestimated how much value people found in these videos.

I’m not going back to individual videos for each light, but I am thinking now of perhaps making some compilation videos showing off lights that have performed exceptionally well in my testing (for a given battery type, or use pattern, or emitter, etc.). That would give me the opportunity to work out any kinks in my descriptions or in the experience of handling the lights ahead of time (as any compilation video would be coming out after the reviews, not concurrently with them).

I’m still mulling the idea over, but please leave me a comment here or on the channel if you can think of something that would be particularly valuable for a video.

Any snark about outdoor beamshots will be promptly ignored. 🙂

New and Improved

Welcome to the new and improved, as of 2023.

The last time I revamped this site was over 10 years ago (back when CSS were all the rage, see the old screenshot above). 🙂

That old site was serviceable enough as a repository for all my reviews on CandlePowerForums (CPF), plus some background info and an overview of my review format. But it was very limited in functionality, since it was largely manually encoded in html.

Now that I’ve decided to start reviewing again, and post my own reviews here, I needed a significant refresh. So I dusted off my WordPress template, and rebuilt it for flashlight reviews. I will admit that even this template is a little long in the tooth now. But I find its “magazine format” convenient for posting reviews and articles (like this post), with everything easy to find on the main page and sub-pages.

How to Use this New Site

The main navigation bar at the top will take you to everywhere you need to be. As you mouse over each header tab, a sub-menu will open if there are multiple background pages to view. All the content from my old flashlightreviews site is still here, much of it updated and revised to reflect my new approach and format. Hopefully you will find the site’s interface easy to navigate.

The Reviews tab is the main source of action – all my new reviews will be listed there, as well as historical links to all my old CPF reviews. The new reviews posted on this site will be easier to navigate than my old forum reviews, with in-page links to the major sections listed right at the top. Much of the actual data will be directly integrated into the reviews now (i.e., true text tables, not images), and should display well across a range of devices.

One new bonus feature that I am able to offer is a full database of all the key measures of the lights I am testing. Everything you need to compare and evaluate the individual flashlights will be contained within the actual reviews. But I thought I would offer this little something extra for those who are kind enough to make a donation to support my flashlight testing.

You can check out my How to Use the Database page to see what exactly it provides, but it’s basically a searchable and scroll-able table with all the key measures for all the flashlights I’ve tested (beginning with this website redesign in 2023). It also gives you a sneak peek at what I’m currently testing (or planning to review), as I plan to update the table with specs and preliminary results as I go, ahead of the full review posts. And you can download a full copy for your own personal use, in excel format.

Access is easy: all you have to do is make a minimum $10 PayPal donation to my flashlight review fund. 🙂

Once you have made the payment, you will be provided with the password to access the database page. The first time you click on the main database page (through the main menu, or link above), you will be asked to enter it.

Your access will expire at the end of the next full calendar year after your donation is received (i.e., you will have the remainder of the current year and the next full calendar year of access for a single donation). The site has cookies enabled, so the password will be remembered for up to one year in your browser (but do keep a record, so that you can access it across multiple computers, etc).

All I ask is that you please don’t share it with others, or download and distribute the database from this site. I’m happy to make the database available to you as my little thank you for your generous support for my reviews. Note that as before, I do not accept payment for my reviews, and fully fund this website and all my review activities out of my own pocket.

RIP, old, long live the new site – and the new reviews!

My (Limited) Return to Flashlight Reviewing – Part II

Following on my Part I post, you may be wondering why I’ve decided to return to flashlight reviewing after a six-year hiatus.

I’ve lurked a little over the intervening years, to see what was new and emerging. A few innovations caught my eye, but nothing to really draw me back. In particular, emitter efficiency appears to have barely budged over the intervening years. Then I noticed how all the manufacturers had begun to produce 1×21700 lights.

So what’s so special about this battery class? The ICR chemistry is the same as standard 18650 cells – which had maxed out at ~3,400 mAh during my earlier reviewing years.  But the slight physical size increase from 18650 to 21700 means you can pack a lot more capacity in there – up to ~5,000 mAh, as it turns out.

Why is that significant?  Of course, extra capacity will translate into extra runtime when driving an emitter to the same level. But ~3,400 mAh is plenty of runtime for our very efficient emitters, even on their higher levels. No, the interesting point to me what was what this meant in terms of battery energy density – and thus how hard you can drive an emitter.

There are two main ways to increase the power density of a lithium-ion battery: improving the chemistry of the lithium battery itself (which of course would be hard to do with such a mature technology), or simply increase its physical size. Given the cylindrical shape of the cell, 21700 adds quite a bit more “oomph” over 18650 dimensions for a fairly nominal increase in overall battery/flashlight size. As an aside, you can apparently thank Tesla for this innovation – their early vehicles were based on existing 18650 cells, and they apparently convinced Samsung to build the 21700 class for higher energy density in their newer models.

There are two main limitations to how hard you can drive an emitter – how fast you can draw away heat (to prevent damage to emitter/circuitry), and how fast you are depleting the cell.  Back when I was reviewing, newer lithium ion battery chemistries (like IMR) would allow you to sustain higher discharge rates – but these cells had much lower energy density, translating into lower runtimes (and they typically lacked protection circuitry).

But 21700 hits a sweet spot with standard ICR chemistry in that its higher energy density means you can safely sustain higher discharge rates. So you can drive the emitter harder – at least for short periods of time, before thermal management mandates decreased drive levels. And you can still use standard protection circuits for safety.

To put things in context, back when I was reviewing lights, the compact 1×18650 class had pretty much topped out at ~1,100 max lumens with emitters of the day. But with 21700 cells and the latest emitters, you could easily drive the lights to 2,000, or 3,000, or even 4,000 lumens for brief periods of time. That’s a lot of output in something nearly as compact!

So here was this entirely new battery class that had taken over the field, and a whole new range of lights capable of super-high output. That certainly caught my attention.

But that wasn’t all – most major manufacturers were now bundling lights with branded 21700 batteries included. And these batteries featured built-in charging capabilities through ubiquitous USB-C port connectors (or, at a minimum, the lights had such features). So, stand-alone battery chargers were no longer required. Having gifted a lot of lights in my lifetime, needing to provide quality battery chargers (and training on how to use them safely) was always a very limiting (and costly) endeavour.

But now we have the conditions to produce the ultimate holy grail of every-day carry (EDC) flashlight technology – a reasonably compact light, with moonlight to multi-thousand lumen max output capabilities, all in an easily rechargeable fashion with no special gear required. One light that could serve as everything from your bedstand light to your outdoor search light to your glovebox emergency light. Hot damn, now we are on to something here!

As an aside, the use of bundled 21700 batteries is not necessarily a boon to all – while great for the general consumer, flashaholics are likely to find this a bit frustrating in practice. The reason is that due to the nature of very exacting tolerances when fully tightening the tailcap (since most lights have anodized threads), it’s possible that few (or no) other battery brands will fit and work in a given light. There is of course the general issue of whether or not there is an integrated charger on the battery (which makes them longer 70 mm), but also whether or not reverse polarity detection is used (and if so, how raised of a button is needed, etc.). The end result is that unlike the old days of 18650 lights – where most batteries would fit and work, once you clarified whether a button top was needed – a lot of the new 21700 lights effectively have a custom battery that can’t be easily swapped out.

In any case, my curiosity was piqued for this class. When I started looking at existing reviews, I was quickly frustrated to see relatively little in the way of direct comparative testing. Sure, there are many quality individual reviews out there of different models – but how easy is it to directly compare performance from existing reviews? Sadly, direct multi-light comparative testing seems to have fallen by the wayside in the years I was away.

So, here was a fantastic opportunity to comprehensively compare an entire new class of lights that have wide implications not just for the enthusiast community, but for everyday users as well.

I dusted off my old lightbox and ordered up a few compact 21700 models. I was able to recalibrate my lightbox for the higher output (see updated lightbox info here), giving me confidence that I could directly compare new 21700 lights to the old 18650 models. I then reached out to some of my old manufacturer contacts, many of whom were interested in sending me some specimens to test and review.

That testing is ongoing, and I will soon start posting my new reviews of 1×2700 here on

My reviewing format will be tweaked a little bit too. No, I won’t be producing glossy magazine photos of lights – just the basics to show you the build. But my data results and tables will now be more quickly and easily produced and shared. Indeed, even my entire new database will be made available in real-time (check out my How to Access the Database page to learn more).

And I’m also going to start adding a feature I always eschewed – a rating system for lights. Given my focus on this single class-level right now, I think it’s reasonable to finally start offering up an overall score, to allow you to quickly compare to other lights in that same class. If anything, my reviews are going to be more tightly data-focused, with less extraneous material (i.e., no more video overviews). But running my own review site will give me greater control and flexibility with the content – and you will able to post your own questions and comments right here.

What’s next after I work my way through the compact 1×21700 class lights?  I don’t know. I do plan to pick up additional lights here and there, in a curiosity-driven way. So expect to see the occasional higher-output thrower or flooder thrown in, maybe a keychain light or two. We’ll see.

I certainly won’t be returning to the volume of lights I used to test – that wasn’t sustainable. Let’s take things one light at a time for now, and see where this goes.

Be seeing you!



My (Limited) Return to Flashlight Reviewing – Part I

Some of you out there may remember me. 🙂

Beginning in early 2007, I started posting personal reviews of flashlights I owned on the main online flashlight discussion forum at the time, I had initially modeled my reviews after the (now long-since extinct) run by Doug P. (aka Quickbeam on cpf). But there was a distinctive defining feature of my reviews –  direct comparative testing of different models of the same class within each review. I will come back to this point at the end of this post.

My reviews quickly became popular, and by the end of that year manufacturers’ started contacting me to review their lights. Within a year, most of the major manufacturers were sending me lights to review. And by the time I wound down my review testing in early 2016, I had reviewed nearly 600 flashlights (not to mention about two dozen massive round-up comparison reviews, broken down by battery class).

So why did I stop, and why am I making a (limited) return?

The answer to the first part is a combination of life getting in the way and waning interest, for reasons I’ll explain below. As for my return, I’ll cover that in a part II post.

As was likely obvious from my reviews, I have research background. Indeed, one of my innovations was to structure my reviews roughly in the format of a scientific research paper – something that is common now, but basically unheard of when I started. But as a successful professional in my own field, my work responsibilities continued to expand to the point where I had little free time left anymore – and couldn’t handle the flood of requests I was getting.

I was also getting less satisfaction from the reviews. I had found the pace of innovation in flashlight design and performance had really slowed down. Through most of my time as a reviewer, overall LED emitter output was easily doubling every 12-18 months. And those early years saw huge explosions in innovative circuit designs  – with increasingly efficient constant current regulation and tons of specialty modes – and huge experimentation in user interfaces (e.g., visually-linear ramping outputs, intuitive magnetic control rings, etc.). And of course in the beam patterns – as a result of diverse designs and layouts in terms of emitters, reflectors, optics, etc.

But by ~2015, LED technology had largely fully matured, without the previous leaps in performance I had seen. An endless variety of me-too lights crossed my threshold that didn’t offer anything significant over what had come before.

Even worse, I was seeing increasingly the loss of useful features and designs, as manufacturers reverted to simpler and cheaper circuits (but with increasingly rakish physical designs, to distract you from the lack of substance). For example, formerly “hidden” modes were increasingly showing up in main sequences or too easily accessed (i.e., you could far too easily “tactically strobe” yourself now). The very useful “moonlight” modes for dark-adapted eyes were rapidly disappearing. And visually-linear ramps were turning into a joke with speeds so high that you could barely access a couple of discrete levels, etc.

Some of the other key drivers for my reviews had also diminished over time. I have always been singly focused on the truth when it comes to reviewing – by providing accurate, independent testing. While ANSI FL-1 standards were far from perfect, their widespread adoption at least helped to level the playing field in terms of reported specs – assuming makers were accurately representing their lights (which, while far from perfect, did improve over time and were fairly accurate by that point).

Moreover, when I started, there were very few truly independent flashlight reviewers out there. As many others joined the field, and started producing their own detailed reviews, I felt the need for my own personal reviews had lessened somewhat – there were plenty of others out there to pick up the torch (pun intended).

That said, I was concerned about how many other reviewers out there seemed to be more focused on producing glossy-looking outdoor photographs of flashlights than they were on rigorous comparative testing. Intentional or not, these glitzy presentations were serving as free marketing tools for makers. I don’t mean to cast shade on my fellow reviewers here – I believe the vast majority were simply focused on producing the highest quality reviews possible, and they had far more photographic experience/skills than scientific. But the end result was a not-so-subtle shift of reviews being used are marketing tools, which I didn’t enjoy (and didn’t want to be a part of).

The intervening years

I haven’t been entirely absent from the online reviewing world in the intervening years – but I moved on to a (somewhat) less labour-intensive hobby, yet one that involved even more of my quantitative analysis skills and interest: whisky reviewing. 🙂

More specifically, since 2016 I have been running a meta-critic review site for whiskies (, where I integrate reviewer scores in a statistically-rigorous way for popular bottlings. Here is a little background on the methodology, with links through the rest of the site on everything you (n)ever wanted to know about how to integrate reviewer scores (not to mention the actual database, which is based on >25,000 individual review data points). It’s true that I did my own reviews there too, but these were just personal sensory analysis – they didn’t require all the long-hours of testing and review preparation as for flashlights.

To be honest, my interest there has also waned in recent years – ironically for many of the same reasons as I left flashlight testing. With the rising popularity of whisky in recent years (and the unchanged need for extensive barrel aging), the field has similarly become saturated with an increasing array of lower quality bottlings – put out at an ever increasing frequency to distract the public from the lack of substance. And as many established whisky reviewers wind down their own reviewing, and an increasing number of less-experienced reviewers join the field, it has become harder and harder to find the consistent reviewers that I need to build up the statistical models to integrate quality reviewer scores.

It’s ironic in another sense – the one thing I always resisted in my flashlight testing was an overall score or rank of the lights I reviewed. That’s because I wasn’t trying to give you an overall impression of a light, boiled down to a single number.  I wanted to show you how a given light compares to others in its class, on all the independent scales that you may care about, so that you can make your own decision based on the extensive comparative data. Whisky reviewing was quite different – you can statistically divide whiskies into flavour categories by cluster analysis, so knowing the relative quality of a particular bottle in a given flavour cluster was what actually mattered (and where I could add value by developing and maintaining the meta-critic).

So where do we go from here?

Or put another way, why I have come back to flashlight testing?  That question has a number of facets as well, which I think I’ll save for the next post.