Rather than stumble around in the dark asking dumb questions. Can you guys point me to a place on the web that will explain all the basics in regard to lights.  Like what's a lumen, how many do you need in weapon light, how many do you need to see 100 yards, what is xenon, what is LED, why is a 123 battery better than a AA, etc, etc, etc.

Please help. If not for me, think of all the stupid questions you may save yourself.

Grant and Brightflashlights should be along momentarily, those guys are the resident light experts.

You got a question……they got the answer!

The problem is I don't know enough to know what to ask.

A FAQ thread is actually a pretty good idea.  It could include things like

advantages and disadvantages to xenons and LEDs
battery types and power
which lights are suitable for mounting on weapons
other stuff

I wish I knew enough about them to start one.  

Many of your questions (that aren't firearms specific) are answered on www.CandlePowerForums.com but there is no FAQ easy to find at the moment. You'll get a lot of detail (too much?) over on CPF.

If nobody else chips in before I get home I'll have a go at answering them.

Al

Quoted: Rather than stumble around in the dark asking dumb questions. Can you guys point me to a place on the web that will explain all the basics in regard to lights.  Like what's a lumen, how many do you need in weapon light, how many do you need to see 100 yards, what is xenon, what is LED, why is a 123 battery better than a AA, etc, etc, etc. Please help. If not for me, think of all the stupid questions you may save yourself.

A lumen is a light output measurement unit.  More lumens means more output.  Candlepower is an intensity measurement of light.

Weaponlights need at least 50+ lumens.  50 is on the low end.

At 100 yards.... depends on what you are wanting to see and your eyesight.  Typically at 100 you are getting into the range of small spotlights (Surefire M500 or M6 or true spotlights).

Xenon refers to the gas inside the bulb.  Typically a tungsten filament will have a high pressure xenon/halogen mix to prolong lamp life by slowing tungsten evaporation from the filament.

LED is a light emitting diode.  They are relatively shock resistant as they have no filament to break, but require electronics to function (more stuff inside).  Better LED's use luxeon LED's.  LED's are subject to emitting different color spectra as they have a mostly single emission wavelength that then hits a phosphor plate thingy to give off white light.  They tend to emit less warm colors, but make up for this by providing constant output (regulated LED's).

123a cells are better than alkaline in that they provide a better voltage/capacity drop than alkaline cells.  123a's tend to burn bright during the first 80% of the burn, then start fading away or die suddenly.  AA's in a minimaglite run for a long time, but dim during the whole run.

Edited to add,

What are you looking for in a light, we can help guide you to the right choice.

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