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Question And Answer

AlphaSeries Bulb FAQ

1) What models does the Alpha Bulb fit?

Answer: Alpha will fit these models perfectly: Pelican M6 series flashlights, Surefire 6P, 6PD, 6PD LED, D2, D, G2 Metal and Plastic, M2, Z2, C2, G2Z, Surefire G2, G3, 6P And 9P!. If your model uses a P60 or P61 bulb, then you can Upgrade it to this LED High Output Bulb!

2) How many volts does the Alpha uses?

Answer: Alpha bulbs are made for voltages ranging from 3.6 to 15 Volt..

3) What is the difference between the Alpha G10 Supra and the Alpha 10 G-Shock Bulbs?

Answer: As with all Alpha products, both are military spec bulbs…but The Alpha G10 Supra is a single stage LED bulb. The Alpha 10 G-Shock bulb has 3 brightness settings a flashing/strobe features.( 5 modes in total)

WHAT IS LUX?

LUX - is the unit of measurement for light intensity. One lux is equivalent to the light level of a single candle light. The symbol for Lux is lx.

Lux- is a unit of illumination, equivalent to 0.0929 foot-candle and equal to the illumination produced by luminous flux of one lumen falling perpendicularly on a surface one meter square. Symbol: lx Also called meter-candle.

Basically, it's a unit of light measurement. Higher the number, brighter the light source.

The unit of lux (illuminance value) tries to relate the actual energy per unit-area falling on a surface to what the human eye perceives.

LUX vs. Lumens

The difference between the units lumen and lux is that the lux takes into account the area over which the luminous flux is spread. A flux of 1000 lumina, concentrated into an area of one square metre, lights up that square metre with an illuminance of 1000 lux. The same 1000 lumina, spread out over ten square metres, produces a dimmer illuminance of only 100 lux. Mathematically, 1 lx = 1 lm/m2. Many people have thought to use this mathmatical calculation in order to calculate the lumina of a projected beam device such as a flashlight/torche. Some have distanced themselves from a surface sufficient to spread a flashlight beam 1 meter and have made luminia calculations based upon the lux reading taked. This however is scientificaly imposible as such deviced always have a factor of “wasted” or “cascaded” light, making such calculations erroneous. Such calculations will generally be inaccurate by as many as several hundred percent. Therefore there is no scientific field calculation which can even remotely convert lux to luminia (lumens) when discussing flashlight which utilize polished or coated reflectors.

Why is Lumens and acceptable rating for a theatre projector, but not a flashlight?

The reason Lumens is an acceptable rating for theatre projection devices and not for flashlight projection devices is quit simple.

Theatre projection devices utilize optical magnifier lenses to accurately eliminate 99% of “cascaded”, or “wasted” light. This means that the light is being precisely focused onto the surface area intended, and almost no light is lost outsite the area of focus.

Although there are some flashlights which utilize high quality optical magnifier lenses to project a beam, most do not.

99.99% of all flashlight including the most expensive models available today, use highly polished/coated reflectors.

Light projection devices which use these highly polished or coated reflectors (such as almost all flashlights) have cascaded light which is not part of the center beam or “hot-Spot”. This may be by design or because of poor quality. Between as much as 100 and 1000% of the light emissions may therefore be lost in the cascaded light. Thus explaining for the gross performance variation for lights bearing the same or similar lumen ratings.

Typically, companies putting more time and money into the development of their flashlights achieve much higher lux ratings at much lower luminia outputs and therebye increase the efficiency of their lights while also increasing their run-time and battery life. This causes what therefore is known as a “brighter” light with regards to visual performance, to actually have a smaller impact on the natural environment due to the saving of energy through this efficiency… Luminia increase therefore generaly means more power consumption, while lux increase may well be a sign of better manufacturing if battery efficiency is increased.

Luminia has been a chosen rating by many flashlight companies in recent years to the surprise of the scientific community. Whereas lux is a quantifiable performance rating which can determine the actual distance a projected beam can travel, and is therefore an acceptable and accurate performance rating,… luminia, or lumens, have very little to do with the calculatable performance of any such projection devices which use polished reflectors. This explains why no two beam projection devices(or flashlights) which have the same “lumens” rating actually perform the same;…many differing in projection strength as much as 1000%.

Luminia, or lumens is therefore the perfect rating for a flashlight if you want to hide the actual projection performance of a beam. Lux is the optimum characteristic if actual performance of a beam projection device is desirable.

LUX VS FOOTCANDLE

One footcandle ≈ 10.764 lux. The footcandle (or lumen per square foot) is a non-SI unit of illuminance. Like the BTU, it is mainly only in common use in the United States, particularly in construction-related engineering and in building codes. Because lux and footcandles are different units of the same quantity, it is perfectly valid to convert footcandles to lux and vice versa.

The name "footcandle" conveys "the illuminance cast on a surface by a one-candela source one foot away." As natural as this sounds, this style of name is now frowned upon, because the dimensional formula for the unit is not foot • candela, but lumen/sq ft. Some sources do however note that the "lux" can be thought of as a "metre-candle" (i.e. the illuminance cast on a surface by a one-candela source one metre away). A source that is farther away provides less illumination than one that is close, so one lux is less illuminance than one footcandle. Since illuminance follows the inverse-square law, and since one foot = 0.3048 m, one lux = 0.30482 footcandle ≈ 1/10.764 footcandle.

In practical applications, as when measuring room illumination, it is very difficult to measure illuminance more accurately than ±10%, and for many purposes it is quite sufficient to think of one footcandle as about ten l.