BackBlast's research and musings

Many people to most people have a hard time laying out any kind of real money (more than $20..) for a flashlight. I'm attempting to show you what the higher end lights have to offer you for that money. Please note that not all high end lights have every nice feature you could want, but this is just an example of what is available.

Materials, threads, finish.

Nicer lights often have higher grade materials and finish. Most all lights are aluminum, but the grades of aluminum can vary. Nicer lights can have 7075 series aluminum, which is harder and better for the application, especially when trying to save weight, than the cheap 6061. Chinese lights many not even have a respectable 6061 grade as Chinese sourced materials are infameous for not even meeting material standards. Cheap lights can have rough or thin threads that are hard to manipulate or worse, wear out after modest use. Once the threads are toast your light is not very useful.

Most lower end lights (Maglite included) use Type II annodizing. Type II can be colored any color the manufacture wants, so it's very color flexible. The thickness also varies, Maglites have a nicer thicker layer, and most cheap china lights are very thin - barely enough to color the light. Higher end lites have a Type III hard annodizing, which is usually a matt finish and black or green/olive drab in color. Type III is significantly thicker, and will result in much better wear resistance against say, keys. A Type II light will eventually have the finish stripped by keys in a pocket, a Type III light will not. The surface durability is mostly cosmetic. The biggest win is probably annodized threads, which help give them longevity under extensive use.

Switches

There is a whole range of possibility here. Low end china lights often have no switch - a twist interface. This is extra hard on threads to be used so much. With cheaper threads you can wear it out with use. Better machined lights hold up longer with a twist interface.

Switches are generally rated for X actuations. Low end manufactures pick cheap switches to cut costs. When you don't use a light very often, this is fine for most consumers. If you're expecting your light to put up with a lot of hard use, it's undesireable. That said, there is an ugly side to even most high end switches. High end US manufactures, like SureFire, still have trouble with infant switch mortality rates. That is a switch which passes QA but still fails early, though the switch is still able to meet it's desire "average" failure rate. It is advisable to purchase spare switches for higher end clickly lights and most higher end manufactures make these available for sale.

Light Source

Most people these days are fairly well educated on the merits of LEDs over incandescents, so I won't even touch that. What people are not educated well on is the idea that not all LEDs are created equal. There are two general families, 5mm LEDs, and power LEDs.

The cheapest of the cheap are low end 5mm LEDs. Often, simptoms are a poor phosphore coating. A little background on LEDs. White LEDs are built using a blue LED die, and then applying phosphore coating like a fluorescent light to cause some of the blue light to change to green, yellow, orange, and red. An LED that does not have a good coating will show up very very blue, and consequently, has poor color rendition. Sometimes the phosphore will not be evenly applied, which will generally show up with blue and yellow swirls on a wall, giving inconsistant color rendition. Cheap LEDs are often not very efficient either. This may not matter to a user, poor color can still help one navigate around the house at night. Or read a book. But what if you are trying to ID something more important? A potential hostile in your home, the color of the inside of meat you are trying to cook, a particular medicinal flower or plant you are searching for in the woods at night.

Even good 5mm LEDs generally don't have really great phosphore coatings, but the good ones are marked improvements on the cheap ones. I've only seen good LEDs on good lights.

Power LEDs are a different animal. In the past, there were no "cheap" power LEDs, but that is changing. Power LEDs, generally, have better phosphore coatings for more even white light. A light will typically only have one power LED vs several 5mm LEDs. The trick with power LEDs is usually heat management, and light management.

Heat Management

Cheap lights do not manage heat well. They will insulate the LED instead of trying to thermally couple it with the host. MagLEDs are an example of this. The LED is not effectively thermally coupled to the aluminum body (which would be an excellent heat sink), which will cause several side effects. Hot LEDs are less efficient, they use more power, and they wear out faster. Maglite has elected to include a thermal probe and simply back off the power to keep the LED below a specific threshold. This manifests itself as lower output after 5 minutes or so of higher output before the LED warms up. The cheapest of lights totally ignore thermal issues and often burn out LEDs (power or 5mm) quickly, but even before they burn out completely their performance is severely degraded over time.

Light management

5mm LED are typically "unmanaged", the acrylic lens is left as-is and not redirected, or shaped. Power LEDs usually go for a reflector or a lens. The reflector beam profile is a compromise, a spot and spill. A lens is usually one or the other, a wide beam or a narrow beam.

(Warning: tooting my own horn) I've designed a light to eliminate the compromise, give you the beam profile you want when you want it (100% spill, 100% spot, or any combination you like). Unfortunately I could never make the numbers work to sell it profitably.

Moving along, reflectors are included in most lights as it is generally the best compromise for most uses. Higher end lights will have nicer, stippled reflectors which yield a better, smoother beam, that helps in object recognition over the ringed patterns of smooth reflectors. Higher end windows (The glass in front that allows light out but protects the light from the environment) have anti-reflective coatings which allow ~10% more light through the front than a window without the coating. Some higher end lights use thicker/harder windows to also resist scratching. Including high grade glass, sapphire, or diamond coated glass. This keeps the business end of the light in good shape and highly efficient through hard use. Scratches significantly hurt your efficiency, as does a window without at least an internal anti-reflective coating.

Electronics

LEDs are current based devices, as opposed to the voltage based. They also vary significantly sample to sample exactly how they behave. And thus typically require good electronics to "regulate" that power to conform to the LED and output the desired amount of power. It is desirable to have nice electronics to preserve the LED and make it perform well with the available power.

Low end lights skimp to the very basics in electronics. This can be observed in cheap china lights that use 3 AAA batteries. These typically only use the LED(s) themselves and a single resistor (if that) to limit current. Resistors are inefficient power converters, 3 AAAs contain about the same amount of power as 1 AA, at a significantly higher size, weight and cost.

In designs that include more sophisticated boost circuits, in cheap lights they are often very inefficient (sometimes 50-60% efficient), only *half* of your power (or less) is going to the actual LED.

Cheaper electronic designs also often overdrive LEDs, well beyond spec, without heat management. Which will degrade performance quickly.

Better designs are more efficient, manage heat, and can occasionally have nice features like multiple levels which allows you to adjust the light level to circumstances to save of battery life, and occasionally to preserve night vision.

Bogus marketing

Often times manufactures will overstate output and runtime. Even higher end manufactures may not use the same basis for their numbers, but usually they're not completely based on fiction. A better source for hard and normalized data would be the many online review sites and forums.

See http://www.candlepowerforums.com as the premier flashlight forum. Be careful, it is a hobby that can really suck you in if you let it.

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