BlervÂ’s Semi-Comprehensive Flashlight Guide (VERY Long)

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Blerv’s Semi-Comprehensive Flashlight Guide (VERY Long)

Postby Blerv » Sun Jan 13, 2013 6:49 pm

Disclaimer: There are plenty of guides and wiki’s on the internet. There are forums completely devoted to the topic that this article will discuss. My efforts are simply to share EVERYTHING I know about flashlights hopefully in a way people can find useful.

The “Semi-Comprehensive” means I will not be right 100% of the time nor believe to be the end-all authority on the topic. I will be updating this with new content and editing it for flow and accuracy. Please let me know if anything needs to be fixed.

Table of Contents:

• Intro
• Types of Flashlights
• Anatomy of a Flashlight
• Quick Guide to Batteries
• Flashlight Performance
• FAQ – To be Continued!


Flashlights have been a household tool for almost a century. The idea of having something small, light weight, and quite bright that can fit in your pocket though is a pretty fresh concept. Almost on par with computers technology of these tiny marvels is constantly changing and difficult to wrap your mind around at first. Rather than confuse you with rhetoric I hope to explain this in a practical way that anyone can follow and enjoy the comfort of knowing you have a pocket light to keep you safe.

Why carry a flashlight?

It’s a fair question to ask. If you carry a pocket knife(s) it’s very likely you also carry a ton of other gear. A phone, keys, pen, a huge wallet, multitool, and many other things which make you rattle when you walk or make you uncomfortable when you sit. The problem is that if you ever are in a situation where you NEED light very few things will work as improvisational tools. A cell phone might but at the expense of communication with the outside world. A light can aid in escaping vision-impaired locations, prevent dangerous slips and falls, and even potentially steer clear of predators. With lights that weigh less than a disposable pen (and relatively inexpensive) they should be considered by everyone.

Where to start?

Start with a problem and determine a solution. It’s the most practical way to go about life and works great here as well.
The best way I can figure is to explain the various types you will likely be choosing from for EDC, coat pockets, or the truck. I won’t discuss lasers, HID search lights, or even incandescents. Then we will talk about the various parts of a light and generally (but not absolutely) how they impact performance. Then I will l will give you a quick guide to batteries and how they impact ability to solve a specific need. After that we will put this information into a practical guide to performance. Lastly I’ll put a number of basic questions that plagued me for years and you have probably heard many times with some curiosity. If you have any questions please let me know!

Types of Flashlights:

Just like with pocket knives there are various categories I would place lights into. Mostly this comes down to if you can carry it on a keychain, pocket, coat pocket, or you need to carry from place to place. Otherwise it comes down to how a light is made similar to how a Spyderco Native is made compared to say a Chris Reeves Sebenza. How production model impacts performance, reliability, and ultimately price.

Budget Lights: Anytime someone is trying to sell you a light at the hardware store counter this is a budget light. They are cheap and likely brighter than most the lights you remember from 20 years ago. They are small. Usually they have at least six 5mm LED’s that glow purple :p . Often these budget lights are found online from places like DealExtreme. These are cheap and can provide some great performance per dollar. The downfall is often the threads are gritty, soldering isn't amazing, and occasionally (the really cheap ones) can show up and not work without a bit of elbow-grease, or a trash can. These are always Chinese and that isn’t a bad thing as most lights come from China; like the Tenacious though you ultimately get what you pay for.

Quality Lights: Like I mentioned you get what you pay for. These come in real boxes with instructions and warranties. A Chinese light for $50-$100 is usually outstanding, especially if from a notable brand. They can fail (as can anything) but your chances are exponentially lower than those from the bracket above. These also provide ample performance. Surefire is what I would consider a quality brand and are American lights. This means they are more expensive but should be respected for providing a quality product. The Harley Davidison to the Honda and Kawasaki street bikes for example (to each his/her own). The key to this bracket is: Bang for your buck, well respected brands, high volume production.

Semi-Custom: There are some lights out there such as Peak LED Solutions which are essentially made from a small shop with a few employees. This isn’t a one-man-band (or woman) but they don’t design a product overseas and receive a wrapped pallet. Usually the warranty is very nice and the quirks are heart-felt. The price is a bit higher and you often have a few more custom options than the major brands. They are selling to enthusiasts primarily.

Host Lights: The most popular is the P60/D26 hose made famous by the Surefire 6p. Essentially people have made lights designed to take the modular light engine Surefire created. This means you can buy lights and custom engines building really anything you want from 200 lumen to 1300 lumen pocket lights. I’ll expand on this at another time but it could be a 10 page article in itself. ;)

Dereelight Javelin head on C2H body, P60 drop-in

Custom: One guy or lady with a lathe making beautiful products. Similar to the Sebenza of lights these range in price, mostly due to materials used. Aluminum lights are pretty affordable compared to custom knives, brass and stainless steel are a bit more, Titanium and Copper are in Sebi world. Terrific pocket jewelry and highly recommended!

Macs Custom SST50 EDC

They also come in varying sizes...

Keychain: Small lights with small batteries. Usually twist operation and limited brightness or runtime.

Veleno Customs 40DD

EDC: These are a tad smaller than most folding knives. Sometimes with clips, sometimes without. These most often come with AAA, AA, CR123 or rechargeable lithium sized equivalents. They can be bright to insanely bright with corresponding runtime. Finding one that “throw” very far can be difficult as I will explain later. Usually sub 1” diameter heads are comfortable in pocket, much larger and you will notice them.

Javelin/C2H, Nitecore Extreme, Zebralight SC51, Peak Logan 123 w/ momentary switch

“Coat Pocket”: My own term for anything about the size of a TV remote with a head up to 3” in diameter. You can get nice runtime and throw out of these and I find them about the upper tier of my own functional needs.

Big LED Lights: Anything bigger than I mentioned above makes for great conversation pieces. They get larger, longer, heavier but also brighter and can really reach out and touch the trees with admirable runtime. For my own uses these aren’t as useful. I don’t own an accurate hunting rifle nor a fashionable duffle bag. 16 ounce lights are heavy in your coat pocket (if they can fit)…trust me.

Elecrolumens "Big Bruiser"

Anatomy of the Flashlight:

I don’t have an electrical engineering background. Without talking out of my hindquarters I’ll explain the basic parts and basic functions. These parts are VERY important; like the human body if you change a couple factors it becomes a totally different organism. Let’s start from the front and move backwards.


The bezel protects the lens from impacts of dropping or in some cases swinging at someone in a defensive encounter. Mostly they just look cool. These range from “defensive bezels” that look like a Klingon war blade to mildly crenelated ones that just seem tactical. Smooth and shallow bezels will not effect the beam quality or rob a bit of your light of a bit of throwing ability Extreme bezels may make your beam look quite odd.


These come in various sizes, shapes and colors. Specifically they are intended to only protect your LED or bulb. Construction wise they can be plastic or glass. Of the glass category they are often specified as mineral glass or even sapphire lenses, these are scratch resistant and sapphire more-so. Plastic lenses tend to scratch easier but also can't shatter if struck violently. Often referred to as “UCL” or “Ultra Clear Lens” are more efficient than traditional glass in allowing light to pass though without interference. For all intents and purposes you won’t have much of a choice regarding the lens and if careful even won’t scratch a plastic one. At least not to the point it would impact performance at a noticeable level.

Diffusers either snap-on, slip-on or fit between your normal lens and the bezel. These can change the color of the beam or in the case of frosted/opaque texturing remove the “hot spot” at a loss of some output efficiency. Great for making a thrower into more of a flood light, or at least not as obnoxious of one.
:spyder: Blake :spyder:

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Postby Blerv » Sun Jan 13, 2013 6:50 pm

Aspherical Lenses are similar to a “fish eye lens” for a camera. These effectively take the surface brightness of the LED and amplify it. This removes almost all the light’s “spill” and resulting in a VERY far throwing search type of square beam. They are almost always glass and add weight to your light. They don’t need a reflector as they act as one.

A SST-50 in a Dereelight Aspherical Lens...with a XR-E the spot is about 1/4th the size

Reflector or Optic
Light without focus is pretty much just ambient glow. A reflector or TIR (total internal reflection) optic gives a LED focus. While some LED’s work better with certain reflectors/optics just know the terms are essentially interchangeable and rarely a choice for the customer. Stippled reflectors are called “OP” or “Orange Peel” which smooth out some of the beam’s artifacts making it more appealing to the eye. Smooth reflectors are often referred to as “SMO” and result in maximum throw/range at the expense of beam quality. If looking for peak performance and distance go SMO, if making a nice floody light OP or SOP (semi-OP) is a good path.

Generally the wider and deeper the reflector the further the “throw”. The more narrow and shallow the more “flood” you get. There are other factors which I will explain in the LED section.

A light without a reflector or optic is commonly referred to as a “Mule”. The LED is simply covered by a lens which allows them to be shorter and often fit more LED’s on a single board. There will be no “hot spot”, or large bright center circle, and no “spill” being the outer dim rings. The opposite to an Aspherical Lens you will simply get massive even flood lighting at an expense of range. It’s the sawed-off shotgun of the light world.

Light Emitting Diod, aka “LED”

4Sevens Maelstrom S12 (SST-90 LED)

The LED is the heart of the light. It’s a semi-conductor which has a set forward-voltage which is starts working at and then gets brighter with more voltage and current. The larger the LED the less intense the surface brightness on average (if comparing like for like). You can run these larger units typically much harder and they are often more efficient so they produce more overall light for what they demand from the battery. Smaller LED’s have more intense surface brightness which means per inch of reflector they can throw further with less current (juice from the battery). Compared to modern units they tend to be a bit less efficient for the same amount of current. Here are some common ones you will encounter frequently and how to read them:

“Cree XM-L U3 Cool White 6500k”
[Cree] [XM-L] [U3] [Cool White 6500k]

[Maker] [Model] [Output Bin] [Beam Color and Temperature}

Above is a typical high output LED from Cree. A very popular maker and a very popular LED due to it’s efficiency and ability to take quite a bit of current with proper heat-sinking. Since brightness is a factor of efficiency x current (with inefficiency taken into account) this means it can get VERY bright and doesn't cost a ton of money to make a light with.

Further from Cree you will see a letter and number, this is the output bin. That means for a set amount of current (usually 1amp) a U3 should be brighter than a U2 for the same LED model (XM-L). These rankings go alphabetically then numerically. The next bracket is related to the output bin because cooler lights are more light efficient than warmer ones which are far more efficient than infrared or ultra-violet. If you buy a light with a XM-L and it has a T6 that means either the maker is using older/discounted LED’s or a warmer tint like “Neutral” which is usually 4500-5500k in temperature. If it’s a T2 most likely it’s a “Warm” tint like 2700-4000k and thus even less efficient for the same amount of current and voltage. The advantage being this will look more like a very bright incandescent which is appealing to many people. Additionally Cree often has a letter/number indicating tint such as 4B for Neutral White. You can look up this chart but essentially this further defines the color tint estimation.

High-CRI stands for “high color rendering index” and is usually ranked from 80-95. Incandescent lights are as close to 100 on their rating system but less efficient in actual use with limited bulb lifespans. Since High-CRI tends to be warmer in tint the efficiency tends to be lower. They are great for situations where accurate color at night is necessary or the user simply likes warmer accurate color. Often cool white will bleach out colors and make everything seem “creepy” (it’s a technical term ;) ). Blue tints turn a normal night scene into a horror movie. Since our eyes read light output logarithmically instead of arithmetically you need approximately 4 times the brightness to notice a 2 times brighter setting; this makes tint and efficiency often more important than big marketing numbers.

For reference: Cree XR-E cool white, Cree XP-G neutral, Cree Warm High CRI

Popular LED’s

Cree XR-E: A very small die and mostly used for cheaper lights or situations where an aspherical lens is incorporated as they only use surface brightness for light throw. These are considered low efficiency LED’s these days and have a very low maximum current.

Cree XP-E/XP-E2: A bit larger than the XR-E and essentially it’s replacement. They are usually more efficient and can take much higher current loads for more brightness. The XP-E2 was recently released and is more efficient (about 20% bin for bin) and seems capable of even higher loads making it a great thrower LED for smaller reflector lights.

Cree XP-G/XP-G2: A bit larger than the XP-E/XP-E2 and capable of higher current. It tends to be more efficient, especially in the case of the XP-G2 (about 20% bin for bin more efficient than XP-G). This LED if used in the same reflector as the XP-E or XR-E will result on average with more output and a larger hotspot but at an expense of some throwing ability. The spill (secondary rings of light) will be brighter as well. It’s a nice average LED and with the next generation capable of nearly 500 lumens.

Cree XM-L/XM-L2: The replacement for all intents and purposes to the SST-50 (which mostly replaced the MC-E). This LED is larger and even more efficient than the XP-G/XP-G2. Overall this if put in the same reflector as the XP-G will be even brighter and more floody; capable of easily 800+ lumens with an aggressive driver.

Cree MC-E: A mostly antiquated multi-die emitter where each die is about a quarter the size of the total body. This originally was used for heavy flood and output situations and could see output of well over 500 lumens.

Luminus SST-50: An expensive LED and for most applications the precursor to the Cree XM-L. It’s quite a bit larger and thus will throw a bigger hotspot with less intensity at the center point (candela or Lux). They can handle quite a current load and in some cases are still quite powerful.

Luminus SST-90: About the largest LED you will find in a modern EDC type light. The Foursevens Maelstrom S12 (and whatever they call it now) uses this. It can handle very high current loads and is a common thrower for larger lights. The hotspot is enormous and the spill is bright. It’s expensive and a heat nightmare; for smaller lights it’s pretty much just a flood lamp so there are better options.

Nichia 119 and 219: High CRI LED’s which range from typically warm (119) to typically neutral (219). The 219 uses the same footprint as the XP-G/2 and is a common replacement. It’s the highest CRI rated LED at 95 and since it’s neutral it remains quite efficient. The Cree High CRI is similar in tint to the 119 and very warm, also very inefficient comparatively.

Driver and board: More information added 1/17/13 HERE

The driver and LED are mounted to a board which ranges from copper to to aluminum or other composites. This unit sits between the battery and reflector and works to bring the light to life.

The driver acts as the brain just as the LED acts as the heart. This part determines how much battery voltage/current is used, how the light is regulated, how many modes you have, if you have mode memory, built-in thermal regulation, and so-on.

Direct Drive

A very simple system of a light matching the voltage to the LED. These can be very reliable with lack of additional parts but also dim over time as you are just feeding power with some kinks in the house along the way. Too much voltage/current and the LED toasts; not enough and it won’t light up. The amount of batteries and voltage of those batteries are very important their internal resistance along with the light’s own resistance will determine the performance of the light. There is no driver to suck voltage which makes them (when done right) potentially very efficient. If multiple cells are used they have to be up to the task (max current discharge rate). *there are drivers with direct drive/non-regulated mannerisms but more for modders.

Linear Driver or Current Regulator

With an addition of a few small chips (like AMC7135) current can be increased in 350mah intervals. This allows a maker to set current for "high", lows are controlled via PWM. These drivers are most handy with voltage closest to the Vf/Forward Voltage of the LED. Extra voltage/amps is bled off increasing heat, too much can even fry the chips. The cell(s) have to be up to the task (max current discharge rate).

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Postby Blerv » Sun Jan 13, 2013 6:50 pm

Boost-Driver aka “Step-up Driver”

Since most LED’s used in modern lights need 2.9 – 3.7 volts (it’s “forward voltage&#8221 ;) to even light up often a battery has to be assisted. A single AA alkaline under load only generates 1.2v yet with these drivers can operate a LED at a diminished capacity. In the scenario before if you were to add another AA you would go from 1.2 to 2.4 volts, even with the driver eating some of your voltage due to heat this effectively will double the output for the same amount of runtime. Three AA’s would be 3.6v and may not triple the output but will certainly assist. The cell(s) have to be up to the task (max current discharge rate).

These drivers are usually rated at .8-4.2v meaning you can run anything from a single AA to a rechargeable lithium (3.6-4.2v each). Most EDC lights use these drivers and with a Cree XM-L you can run a variety of batteries. A single AA for 100 lumens, a CR123 (3v) in a screw-on battery tube for 280 lumens, or even a rechargeable battery like a RCR123 or 14500 (AA size) for well over 500 lumens. Typically these drivers over about 3.6v, or whatever is the forward voltage of the LED, will often go into direct drive and will feed the LED all the current the battery can provide. Often you end up losing certain modes, the brightness per mode is different, and runtime goes from about an hour to perhaps 15 minutes. In some cases all the benefit of regulation goes out the window for pure, unadulterated, brightness. The ability to run various batteries for different purposes is terrific though.

Buck Driver aka “Step-down Driver”

Most lights run batteries in a series that means the voltage is added while the capacity remains the same. The current load is split between the batteries allowing high-powered lights to use conventional batteries. If the driver is expecting a range of 3-18 volts that means you can poorly run it on a single CR123 (until it sags/drops below 3v), a single RCR123, or 6xCR123. In this situation remember that the load on 6 primaries is much less than one cell needing to do all the work. You can also run 4x18650’s for about 12,000 mah of capacity. Unlike being wired parallel (same voltage, but adding capacity) you do get some benefit to this extra battery capacity, it’s just not as efficient.

This allows a company to make a light that will be pocket sized but also extend to be one or even two feet long for security guards and LEO’s on a very long shift. These drivers are also a bit more efficient than boost-drivers simply because the batteries have more than enough voltage and aren’t taking it out on the batteries. The disadvantage of course is you can’t run less than 3 volts (in this example) or the light won’t turn on, often it won’t reach full brightness until 4v or 5v but flattens out from 5-18v.

Boost/Buck Drivers

These intelligent drivers adapt to the voltage at hand much more efficiently. Frankly I’m sure many manufactured lights use them but I don’t know which. I speculate most that seamlessly (besides output) will accept a single alkaline to multiple lithium batteries without all the usual hub-bub.

Head and body

This is the case of the light. It has to hold all the components and also acts as a radiator drawing heat from the LED. Often modders, if possible, will wrap the reflector and driver in aluminum or copper foil to better sink these two components. Your hand is the final radiator and uncomfortable or not is a terrific way to protect your light. Tests have shown a light on a nightstand on high will get hotter and faster than one held. This same logic holds to your smart phone or laptop.

If your flashlight is not getting hot after a few minutes on high, either…

• The heatsinking is horrible and your LED is screaming in pain
• The heatsinking is amazing and being disippated via cooling vents or electronic thermal management
• The LED is being underdriven which means less heat and light but often more efficiency.


These are either physical simple switches like a block of aluminum and a spring or electronic units. “Reverse Clicky” means connection is made on the release of the button, “Forward Clicky” means connection is made on the pressing of the button. Switches can even be integrated on the side or control modes such as a magnetic ring which interacts with preset driver points.

Other methods of current transfer exist such as QTC which stands for “Quantum Tunneling Composite”. This allows more current to transfer as it’s compressed which allows for almost infinite levels of brightness for twisty lights that compress a battery between two contacts.

Quick Guide to Batteries -- Please read FAQ Section For Further Warnings

The batteries you use are a personal choice. This will impact the performance of the light and associated costs/danger with the realm of high-end flashlights. They will often also impact the size of the light as it can’t be smaller than the batteries it has to hold. In general you should ALWAYS stick to the recommended batteries by the light maker and match multi-cell voltages. Do not put cells of different age, capacity, size, chemistry, or wear together. Always check voltage with appropriate tools when matching.

AAA/AA: Great cells for typical situations. You can get very bright lights these days with a single AAA and terrific output for a single AA. Approximately…a single alkaline will have 1.5v but sag under load to 1.2v or less. A rechargeable battery like the highly recommended Sanyo Eneloop NiMh will come off the charger at 1.2-1.45v but deliver closer to it’s actual voltage at MUCH better current draw resulting in longer life at medium to high loads. Lastly Energizer has disposable lithium batteries LiFeS2 “Energizer Ultimate” which are about 1.75v and close to that under load, they are expensive but have higher capacity than the other batteries.

CR123/14505 (Li-MnO2) “Primary” Lithiums: These are rated at 3v but will sag a bit to like 2.5v. The 14505 is a recent Titanium Innovations primary for the AA battery lights. These are great for cold/hot temperature situations but often rated for about 1c of current draw. That means a 1500mah battery should only supply 1.5amps to a driver to be safe. These account for many of the explosion scenarios with more than one cell…since when you put a near dead and near full cell together they continue to try and supply the same voltage which results in cross-cell charging.

123a LiFePo4: These are often used as replacements to the CR123 in certain applications. First of all they are rechargeable with the right kind of charger. Second they can take heavy draw but not efficiently; the capacity goes down quickly with high amps. Third they are the safest kind of chemistry so while being less energy dense then the Li-Co’s they will not vent/pop with flame or poison gas. Under pressure and treated stupid they have exploded custom lights (extremely rare) but there is no 1300 degree flare. I believe these are about 3.5v off the charger and they sag a bit, at about 3v they are more or less empty. Often these used for Surefire lights. I don’t own any.

17500/18350/18500/18650/26650/ etc: These are rechargeable lithium batteries typically of the “Li-Co”, commonly called “Li-Ion” variety. These lithium batteries use a cobalt cathode (Li-CoO2) for an ideal operating range of 3.6-4.2v. This allows them to easily light up a LED with one cell and more brightness for most applications. The numbers are broken down for example: 18650 = 18mm diameter x 65mm length). Quality cells are rated at 2c which means twice the capacity, per hour of usage. Depending on size you can provide more amps safely at higher rates of draw. The 26650 for example is the size of a C-Cell alkaline and usually about 3500-4000mah (milliamps per hour). That means it can supply safely up to 8 amps to a led! With the internal resistance of this kind of design/chemistry often though you won’t see that much, that and the lights have their own internal resistance. Likewise though, a RCR123 should not see more than about 1.5-2 amps at most since they have about 750mah. Usually these are protected from over/under voltage discharge and max current draw. It's best not to test this though.

In most these sizes IMR's are available aka Lithium Manganese chemistry and my personal favorite. They are not protected but are considered "safer chemistry" as they shouldn't emit flame or toxic gas if (very rare) they vent. These batteries have less capacity than their Li-Co siblings which is a disadvantage in low-draw situations. The IMR chemistry allows for massive current draw to the tune of 8c for a IMR16340 (CR123 size) or more for the larger cells. That means a single small cell can supply up to 4amps of power and drain itself 8 times it’s capacity in one hour. They should be strictly kept from 3.6-4.2 for operating, lower voltage can damage them.

Flashlight Performance

40DD w/ XP-G, Logan 123 w/ XP-G, Javelin/C2h w/ XP-G, Macs Custom SST-50 EDC

Like knives there is benefit and disadvantage to most setups. Any light is better than not having one so that’s the most important thing.

To recap there are a few ways to get massive output (aka lumens or candlepower):

• Efficiency: powerful LED’s with proper heat sinking.
• Current at a proper voltage: The more gas the more fire. Batteries are rated with mah (milliamps per hour), draining a 700mah RCR123 battery at .7 amps means in theory it will go from full to empty in one hour. Draining at 1.5a or 1500 mah means it will be dead in 30 mins (roughly). Roughly a Cree XP-G R5 at .7a is 200 lumens; at 1.5a it’s about 350 lumens.

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Postby Blerv » Sun Jan 13, 2013 6:51 pm

To recap there are a few ways to get throw (aka lux or candela)

Javelin/C2H aka "P60" with XP-G High CRI

• Large, deep, smooth reflectors: Relative to LED size
• LED’s with high surface brightness: Large lights can use a XM-L as a thrower, pocket lights really need something like an XP-E or XP-G driven hard.
• Aspherical Lens: Per dimension aspherical lenses can throw further than normal reflectors simply needing small LED’s with intense surface brightness. They provide small hot spots and almost no spill making them nearly worthless for up-close navigation

To recap there are a few ways to get flood

40DD with XP-G High CRI

• Small reflectors, shallow reflectors, large LED’s
• Orange Peel: Stippled reflectors will smooth the beam without the ugly rings.
• Multiple LED: The lights with two or three LED’s using their own optics will provide a ‘wall of light’ throwing essentially a huge hotspot a fairly long ways.
• ‘Mule’ head: Without a reflector at all you will get low throw, no hot spot, and a very even spread of light. Think a very bright candle aimed in one direction.

When picking a light it’s important to realize your battery life is finite. If you want something tiny and bright (like 400 lumens but AAA sized 10440) it will have about 10 minutes of full-throttle output not to mention a ton of heat! This is only a problem if you don’t have lower settings or choose to ignore these for cheap thrills. A rechargeable Li-Co 10440 will have about 300mah; a larger 18650 light can have around 3000 mah. That’s a theoretical 1 hour 40 minutes from the same LED.

It’s also important to know once your eyes have adjusted even 20 lumens is a ton of light for most uses. Having a “moonlight” mode is handy because at .2 lumens you can run it for days and days on a single battery. Less is more for certain situations. On this same note remember that 4 times the output will in the same light throw only twice as far (while often drawing over 4 times the battery capacity). Our eyes regarding lumens work logarimitically so we need about an 8% overall increase to even notice a change let alone a large impact.

On that same note some people want throwers but rarely need to shine past 50 yards or so. That means their pencil beam while fun is less useful than a proper floody beam. It’s more efficient because lower modes go further, you just see less of the picture. A real pain if you are trying to navigate a walking space and can’t see your feet or peripheral vision as well.

Remember you have to put batteries in this light. If you only run CR123’s those can be expensive if bought at the grocery store. Duracell’s are great but instead of being $1.50 online they are about $8 apiece at the store! Buy online or use lower modes frequently. Or get a light that can use rechargeables if buying batteries is your worst nightmare.

AA or AAA lights can almost always take rechargeables which are high-safety and boringly easy to use. If you throw a bunch of unknown CR123’s into a light it’s possible, if not matched, they can vent and turn your light into a road flare.

Rechargeable lithiums are fun and you can get very high output from them. However, they can be more maintenance heavy with voltage checking, proper chargers, monitoring them while charging, etc.

Lastly remember if you don’t have it on you it won’t be as enjoyable. Buying a bulky thrower is fun if you live on a farm or rural area and have to check on various things at night. If you are a city person unless you want to annoy people on the street it’s nearly worthless. Your $120 light will sit on the nightstand and only see action when you and your friends drink too much.
:spyder: Blake :spyder:

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Postby Blerv » Sun Jan 13, 2013 6:51 pm

** General Battery Warning: Proper handling is paramount with batteries. They all contain volatile chemicals, some of which being poisonous to inhale or when venting can do so with 1300 degree flames. Even "safe cells" when under pressure, say in a steel tube, can cause enough force to turn the lens into a improvised glass scattergun. PLEASE be safe and read as much as possible on the topic **

* Nobody "frequently asks" these from me but it was a good way of randomly throwing some info/opinions around :p *

I've heard about batteries blowing up, is that common?

It's quite rare considering the amount of people using protected and unprotected lithium-ion batteries. Similar batteries are in your cell phones and a laptops.

Most problems occur with multiple cell situations where the voltage isn't matched. As the batteries have to work together if one is drastically low they tend to self-balance and can vent/pop. Another situation is people charging Li-Co cells (RCR123, etc) on cheap chargers and not watching them. They leave a battery on the charger that trickle-charges all night. Lastly some people overtax batteries beyond a safe level. If you use robust batteries for the job (preferably one cell), charge safely, and match voltages you should be fine. Using safer chemistry further minimizes the chances. If the light starts to get really hot at random and is making odd noises get it away from you!

I really want to use CR123's but am paranoid.

For primaries some good brands are Surefire, Panasonic, Energizer, Duracell, and Foursevens. There are others but that's a nice selection.

To match them you really want to get a load tester like the ZTS pulse load testing multi-meter as it will give you proper voltage. Match your primaries in close sets within say 3% of overall charge. 2.95v and 3.00v, etc.

I want a quality light but don't want to deal with specialty batteries, what options do I have?

It's very easy to get at least 300 lumens on two AA's. In fact, Zebralight has a single AA light called the SC52 that does 280 lumens! AAA's can't provide quite the same draw but 200 lumens is easy with two cells. I would get a pack of Sanyo Eneloops at Costco and find a multi-cell, easy and bright.

Can I literally blind an assailant? Is it a good defense to have a light?

The only likely way to blind someone is burn their retinas, pupils, or whatever that part is called :confused: This is quite easy with a laser but hard with a flashlight as they have neither the intensity (heat) or frequency. If you held a light to someone's eye perhaps and definitely could with an incandescent as its possible to light paper on fire with a hotwire mod. UV LED's can have very damaging effects as well but are hardly fight stopping.

Your best scenario in a defensive situation is having the upper hand. People have horrible night vision so knowing where to go is invaluable. It's been a while since biology class but bright light can slam someone's pupils shut like a steel trap for a few seconds. In the dark or under the influence of alcohol the recovery time is delayed further. If you can blast someone in the face its best to blast them literally in the face (or run). If they can't see you they can still hit or grab you. But yes...1000+ lumens with any intensity will give you a **** headache. ;)

How much light is enough?

Honestly 200 lumens with decent throw is a ton of light. You can navigate a dark room using 1 lumen at ease as well. Functionality and appreciation will make you carry the light, that's the most important thing.

Flood vs Throw? I can't decide.

In most cases flood for function, throw for fun. Walking inside a building in the dark doesn't require more than about 50 feet on average let alone 300 meters. While throwers can provide decent spill lighting the hot spots are so intense it can annoy you if for more than a few minutes.

Some of these lights don't have clips. I'm used to the Spyderco way!

You can free pocket them but with a keychain attachment you can also use a Tec Suspension Clip or even a tip-down Spyderco.

Cool White vs Neutral vs Warm?

I adore warm and willingly accept the efficient hit for small pocket lights. Sometimes cool tints are a but green which drives me crazy but not everyone cares. That said, neutral is quite pleasant and a much less brutal hit (10% or so instead of 30% or greater). For EDC my lights only see about 10-50 lumens on average so 200 instead of 400 isn't a personal bother.

What's a good rechargeable battery brand and charger?

AW makes terrific batteries and the most the IMR's I love. Their black/silver are protected Lithium-Cobalt recharges.I have a cheap digital multi-meter I use to check voltage occasionally and don't run them lower than 3.6v.

There is a person on Candlepower forums who also sells through the EDC forum shop (JS Burleys). His "Cottonpicker chargers" are USB powered and amazing with tiny magnetic leads and optional digital readouts.

So what's a P60?

This is a short answer to a potentially long question. I'm more than happy to help specifically if you PM me :) .

In short you find a host that will work with the battery(s) you want to run. Then you find the appropriate P60/D26 (26.5mm reflector) drop-in which range from $7 crap to $60 custom ones. Next you simply unscrew the host, wrap the drop-engine for heat transfer, put the appropriate batteries in, and bingo...custom light!

Single 123 cell hosts I would recommend are the Dereelight Javelin head/Dereelight C2H body or Solarforce L2m. The Deree is smaller with a recessed tail clicky so it will stand on its end; it also has a great wire clip. The Solarforce is bigger but much cheaper and has more aftermarket support for accessories. Either of these you will want at least 1.2v-4.2v operating range. If you find a 3-4.2 it will be very dim on a CR123 depending on how strong the battery is.

If you want a CR123x2 or 1x18650 light the Dereelight C2H host or Solarforce L2 is great. The Dereelight is again more expensive but a but more refined and space efficient. The Solarforce more accessories and dirt cheap. There are various variations of the Solar Force but you should get the aluminum tubed ones as the plastic body does not heat sink well. You could always get a Surefire 6p as well but it won't take a 18650 without being bored out and modded. If you want to run a moderately bright LED and occasionally CR123's go for the 3-6v drop-ins as they will run well off a 18650 too. If you run two RCR123's at 8.4v the LED will likely pop.

It's best to confirm your drop-in will fit the host if either is non-typical. I wouldn't run 2xCR123's in anything hotter than 2 amps on high, preferably 1.5 amps. You can use high in bursts but its a ton of strain. Most mediums are 50% power so even a hot XM-L should be fine but better safe than sorry. A single 18650 often works and will have at least twice the runtime handing the output with ease.

I want a TON of runtime. What can I do?

It's a dumb response but medium or low mode instead of high. If you have a 600 lumen light with any throw a low mode can last 5-10 times longer at 60-120 lumens. Medium can be two hours on a 18650 battery. You could run an extension tube as well with the right driver which would give you a nice club as well :) . I just had a pocket thrower built that tosses a beam twice as far on low as my Peak Logan does on high with a IMR16340. Flood is handy up close but obviously inefficient use of light for an endurance race.

What's the brightest light I can pocket?

You can easily build a 700-1000 lumen light. After that its price tends to climb or its usage declines. P60's aren't great with heat. Take a look at Electrolumens XM-L EDC R.

What are some nice EDC brands?

I like Foursevens Quark, MiNi and Preon lines. Zebralight makes the SC31, SC51, SC52, SC80 and larger SC600 for a great value. Peak LED makes the Eiger, Logan and El Capitan which are real winners. Dereelight Solarforce, Surefire, Nitecore, Fenix, Olight, EagleTac and Sunwayman are all winners by reputation as I only have owned most of those brands.

Really if you pay a decent amount of money and people are generally giving positive reviews your odds should be quite good. Nothing is guaranteed but its a good gamble.

What's the best LED for an EDC light in your opinion?

Cree XP-G or XP-G2 for a throwy EDC. Cree XM-L or XM-L2 for a bright and floody one. Keychain sized lights if equipped with a XM-L usually don't drive them hard and they are floody...XP-G all the way.

What is "PWM"?

Pulse Width Modulation is a way many drivers regulate output by turning a LED on and off about a thousand times per second. It's only a real problem when the frequency is very slow on the lower modes as it makes a shadowing effect that can make people a bit queasy when using the light around moving objects in the dark. This isn't a problem on high or even medium. Some folks are sensitive to it, some aren't. It's like the Tea Cup ride at Disneyland :p . Typically when people say something has no PWM or "bad PWM" they are focusing on extreme examples over current regulation vs PWM. Believe me, if you read up on a light someone will say if its good or not.

Whats the difference between PCB and PTC?

PCB: A protection circuit in the negative side of protected rechargeable (Lithium Cobalt usually) batteries. Protects against over discharge, charge, and over current. Often will reset when placed on a charger.

PTC: A vent that will respond to excessive heat and will attempts to increase resistance to save the battery.

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Postby Clip » Sun Jan 13, 2013 8:10 pm

Subscribed. Definitely gotta read through this.
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Postby chuck_roxas45 » Sun Jan 13, 2013 8:12 pm

That's was pretty interesting reading. Thanks for sharing Blerv.

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Postby xceptnl » Sun Jan 13, 2013 8:29 pm

This one deserves a good read over morning coffee. Thanks for the comprehensive summary Blake.
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Postby Holland » Sun Jan 13, 2013 8:33 pm

nice guide, never realized how much there is to flashlights

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Postby angusW » Sun Jan 13, 2013 9:52 pm

Great write-up. It's nice to see a lot of good info in one area for easy reference. Can't wait for it to expand.

I don't know if it's worth putting it in or not as I haven't bothered reading the datasheet or reading about it on cpf but is the XT-E any good? I see it being sold at Illumination Supply and I'm temped to pick it up for a light I'm thinking of making.
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Postby tonydahose » Sun Jan 13, 2013 10:11 pm

just glanced it over, i will be reading it tomorrow for sure, it looks like there is alot of good info. For someone who doesnt consider himself a flashlight guy i have a surprisingly big collection of them, no thanks to you and your "check out this flashlight" threads where i end up buying another light :p
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Postby Blerv » Sun Jan 13, 2013 10:14 pm

Thanks so much everyone :) . I'm going to clean it up a bit and put more data up there. Your feedback is invaluable.
angusW wrote:Great write-up. It's nice to see a lot of good info in one area for easy reference. Can't wait for it to expand.

I don't know if it's worth putting it in or not as I haven't bothered reading the datasheet or reading about it on cpf but is the XT-E any good? I see it being sold at Illumination Supply and I'm temped to pick it up for a light I'm thinking of making.
Thanks angusW.

I'm not sure about the XT-E, I haven't heard much about it honestly. At first glance it seems somewhere between the XRE and XPG but time will tell when people really get it out and lean on it. I would love to see what you can do with it. :D

Among throwers I just had vinhnguyen64 at Candlepower forums put together a 1.8a XR-E2 p60 drop in. It's quite bright and throws very far.
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Postby 1623 » Mon Jan 14, 2013 7:24 am

As a relative newbie to all that is light, I appreciate you taking the time to share this information with us, Blerv. It'll be handy to reference this right here, rather than trudging through CPF or other sub-forums for info.

Nicely done.

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Postby kbuzbee » Mon Jan 14, 2013 7:43 am

Nice Blake! Really well done (though I didn't get 60% of what you said, I could tell there was solid info in there ;) )

We only have a couple small lights. I bought a Fenix PD30 that I keep in the car and a smaller Fenix for the wife's purse (which she's lost somewhere in a purse swap ;) )

I don't know much about them, though I did "some" research at the time. It hasn't been called on much but it's been fine the few times I have.


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Postby Blerv » Mon Jan 14, 2013 10:27 am

Thanks again folks :)

Yea it's a ton of information. Not nearly "all" of it but probably far more than most people care to read into. Easy access reference and a starting point for further research is the goal.

When you break it down simply there is no need for 15+ pages of nerdism :p . Most people need a light and can find one easily for about $30-45, this is a terrific solution to their goal. Like knives a Delica or Native5 needs no simply works awesome. When people start asking about locks, steels, and philosophy the reading gets thick though.

If anyone doesn't have a light I encourage them to try one out. Like the Jester challenge carry a small AAA light for a week and see what you end up using it for. In the winter time it gets dark around here at about 5pm, lol.
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Postby Pinetreebbs » Mon Jan 14, 2013 10:43 am

Thanks Blerv, that is some good information.

Sounds like you might enjoy visiting Budget Light Forums, there are some awesome lights out there.
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Postby Jazz » Mon Jan 14, 2013 10:54 am

Thanks bro. I'm definately gonna read it more thoroughly. Love flashlights - they are so useful. I use a Preon at work, and it's always suprising how many times I'm using it. Fenix PD10 at home. Other larger Fenixes in coat pockets. Microlight on keychains. What is the keychain model in your pic?

- best wishes, Jazz.

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Postby Blerv » Mon Jan 14, 2013 11:55 am

Thanks Pine :) . Yea I occasionally visit BLF and CPF. Great places. I spend more time at EDC Forums and obviously too much time here :p

Hey Jazz. That's 40DD from Steve Ku (Veleno Customs). He did a run of it in stainless with various options back on the CPF forums. It was such a winner he ended up going production with it. :D

The Quantum DD comes with a small lithium cell battery and special charger, it uses a cool white XP-G and a tiny QTC module for nearly infinite levels of brightness from like .1-100lumens. He recently released his Quantum D2 which is black coated, uses a cool XP-G2 for a bit more output, and has a couple small tweaks. It's a nice little light and great as a necklace or keychain. On high it only has about 8 minutes of runtime but on lower modes it can last at least a week between charging.

Thread Edit: Added descriptions to my pictures.
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Postby Jazz » Mon Jan 14, 2013 2:29 pm

Thank you, sir. :cool:

- best wishes, Jazz.

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Postby Evil D » Mon Jan 14, 2013 2:35 pm

Didn't read it but from skimming it, you've done an excellent job presenting all this info. I'll get back around to reading it when I get time. Nicely done :D
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