I am confused by all the tech talk, help me learn please

Hello everyone. I want to learn about this flashlight stuff. I do not understand all the tech talk and such. Cree, P7, R2, R5, XPG, etc. I mean I see people typing about lumins, lux, etc and I kinda get that. I do not understand how you can tell which emmitter to get just based on my needs. What is the difference between an R2 and R5....for example? Why is one 18650 cell better than another?....it is just a battery.....right? :) Why would you get an XM-L over and XP-G?....for example. Newbies questions here, let the learning begin.

Others with better typing skills will chime in here buy I can point you to about the best resource out there. http://flashlight-wiki.com/ by our own brted.

I would check out http://flashlight-wiki.com/ theres more than enough info in there to get started with.

what lang said.

I will head over there now and have a look around. Thanks for the help.

The other two gave my answer as well. Just one thing to add that I'm not sure that's in there: Generally, with larger die emitters, you tend to get more overall output, however, you don't get as much throw. Not always the case, but you tend to see this correlation. Therefore, with XM-L being a large die, you get great output at the expense of throw. Meanwhile small dies like the XP-E don't have nearly the output but can be easily made into a serious thrower. Xp-G's tends to balance the two.

hope this helps



Isn't throw determined by surface brightness?

In looking at the Flashlight Wiki, if you find there is anything missing, confusing, or wrong, please let me know. Or better yet, sign up with an account and you can add to the articles or just post comments, suggestions, etc. on the talk pages. It all makes sense to me, but I know where the information is and it is written the way I understand things.

As I understand it you are right about surface brightness. The xre and xpe have a higher surface brightness so what sirjohn pointed out would be correct. Everybody’s right. I might not know what the hell I’m talking about though so take that into consideration.

Thanks for this. I am liking the wiki site. It will take some time to get use to things...I mean there is a bunch of info there to take in. Now I am wondering why a flashlight with an XM-L drop-in in it from say Solarforce is around $25 and the same XM-L used in say a 4Sevens light might cost three times as much.....why?

"Now I am wondering why a flashlight with an XM-L drop-in in it from say Solarforce is around $25 and the same XM-L used in say a 4Sevens light might cost three times as much.....why? "

This is why you are here, so you can know when it is right for you to spend more for less, and when it is not. I discovered this at a point after buying a couple of 4Sevens lights. (and many others) The best way I've found to learn is spend a bunch of money on a bunch of lights you don't need.


not easy to learn all of this over night - there is a lot of history that got us here.

for most newer people (myself included ) i'd say we have literally gone from the wright brothers to jets and spaceshuttles in a short time.

not only knowing the terminology of the tech but depending how deep you want to go there is a lot to learn - its easy to book a flight but it takes a while to learn how to breakdown a jet engine

what i mean is you can find what lights or batteries are good but i may take a little mechanical skill and electrical to do a full mod - and some people make it look easy

i remember looking down at the "Everready special" when i got my incan ( incandescent) mag light years ago and thinking this is the best , always alot to learn sir

personally i started reading the comments on deal extreme NOTE: some data may be a bit old look at the date , then CPF , then finally at the best flashlight forum in the world

to actually answer your question i would go for XML for most intents and purposes its the most efficient and brightest per input

if your making a budget one you may want the second latest, CREE XP-G

it term of batteries 18650's are good in general capacitywise i like 18650-Lifepo4 , they have a long standby time at the cost of capacity 1300 vs 3000 to mA (milliamps) and up

the r2 d2 c3p0 are bins values, the "better" the bin the brighter http://www.cree.com/products/pdf/XLampXM_B&L.pdf page 2

i just bought a few and started playing with them. for 8-15usd you can get some remarkable lights and when they are in your hands ideas like "throw" and "flood" start to congeal. what you think might be a good design, like a light that goes from high to medium to low to a strobe light flashing mode to a flashing mode that signals S.O.S, in real life becomes a huge pain in the ass (i know,i know, some will disagree).

buy them, take them outside at night, nothing beats live to see the difference between a uniquefire AA-S1 with an osram led next to a trustfire F20 loaded with a cree Q5-WC ( though, while i like this light, this is the "pain-in-the-ass" user interface i just spoke of), and you have only spent 20usd.

the letters and numbers are esoterica the meaning of which comes over time. try not to forget that the main role of these tools is to efficiently light up the dark with some light, that tends to become obscure sometimes under the weight of choice and tech.

I think you learn pretty quickly that lights are pretty impressive with any emitter that isn't pure ebay chinese fake garbage . so you can buy about any 10 to 20 dollar light you se talked about here on blf with confidence that it will be somewhat impressive .. the proof is that Match(Who does all the cool mods ) just bought a Tank 703 AAA light and is terribly impressed with it .I just bought the stainless steel c3 and the stainless F-23 from T-mart for $11 each and think they are great little lights .

Without trying to promote my own dumb thread..Take the time to look at what other people are recommending . What i was trying to get from people in that thread is ..What are the universally known truthes about flashlights.. just tips to help answer this question for you ..

https://budgetlightforum.com/t/-/2368 some good advice

If you don't have a reflector, that is exactly correct.

yep. I was trying to oversimplify. Generally, the Led manufacturers have had to produce larger dies to get higher overall output. The problem is that larger dies mean much larger surface area. More surface area tends to mean less surface brightness as the light is just dispersed over a much greater area.

You can compensate for that by getting a deep enough reflector to focus that light. With an XM-l, it'll take a pretty deep reflector to get the same type of throw as you get from an XP-E.

Actually throw is more determined by reflector size than by depth; depth plays only a minor role.

And without reflector, throw is determined by total flux and viewing angle, but not by luminance or emittance (which are often referred to as "surface brightness").

I just posted something about throw here.