What lights do you have?

Your question is dumb, and there is no answer on how your light compares

There are lots of formulas (google/wolframalpha are your friends, use them), but it is impossible to determine anything off of the 10,000,000 candlepower number, because candlepower was never standardized, archaic at best, and mostly made up for marketing.

You will need to either compare your light against lights that are independently measured, or to get a light meter, do some measurements and some math to see how your light stacks up.

InfinitusEquitas said:

Your question is dumb, and there is no answer on how your light compares

There are lots of formulas (google/wolframalpha are your friends, use them), but it is impossible to determine anything off of the 10,000,000 candlepower number, because candlepower was never standardized, archaic at best, and mostly made up for marketing.

You will need to either compare your light against lights that are independently measured, or to get a light meter, do some measurements and some math to see how your light stacks up.

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light meter! so there is an answer I guess I should have left the "say it's a dumb question out" because someone once said NO QUESTION IS A DUMB QUESTION and that is true. and yes Google is my friend do you know him?

my question was more curiosity than anything ..Thanks

I always just think of some scientists lighting up countless candles one by one with the spotlight in his hands comparing haha.
"1 candle power ah, ah, ah 2 candle power ah, ah, ah... "

starlight said:

light meter! so there is an answer I guess I should have left the "say it's a dumb question out" because someone once said NO QUESTION IS A DUMB QUESTION and that is true. and yes Google is my friend do you know him?

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Kind of. I met both Larry Page, and Sergey Brin in 2007 :angel:

Tmack said:

I always just think of some scientists lighting up countless candles one by one with the spotlight in his hands comparing haha.
"1 candle power ah, ah, ah 2 candle power ah, ah, ah... "

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That explains all the candles you have.... here is a picture taken of Tmack at his house

They have to calibrate lux meters somehow

lux and lumens are two different ideas.

Lux is how much light is hitting a surface at a particular distance, and can be a useful measurement for how far a light will "throw" light if you have just a bit more info.

Lumens are a unit for measuring how much light is produced by a source overall. You can convert lux to lumens if you know the distribution pattern of the light, and lux values for all points within the distribution pattern. In the real world, though, it is very hard to convert lux to lumens accurately for something like a flashlight. Think it is like integrating the lux values for all points that the light hits.

Lumens has gained popularity as people now realize that lux is all about marketing, and that lumens is what you are actually after.

I think of lux as how concentrated the beam of light is, and lumens as how much light total is being put out.

Haha. Damn mark. I told you not to go in that room.

That's actually my highest lumen light. Every candle in that picture has been dedomed for more throw Btw.

I always thought the company brag about lumens for marketing the light. While lux is a better measurement of how much of the light your actually putting on the target. Hmm.
Guess not.

Read up: http://www.streamlight.com/Documents/ansi/ansi-pres.pdf

I think they screwed up a bit in creating the standard, and not adding a qualifier for the diameter of the area illuminated at half, and maximum distance, as well as the relative lux numbers.

Tmack said:

I always thought the company brag about lumens for marketing the light. While lux is a better measurement of how much of the light your actually putting on the target. Hmm.
Guess not.

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No, you're right. These days, even non-flashaholics understand that lux isn't a rating of how bright the light is, so the manufacturers can't hide behind inflated lux ratings anymore. The advent of multiple household bulb types probably helped this along too. I don't think lightbulbs used to claim how many lumens they produced, but nowdays, anything that is worth anything states a lumens number on its packaging. ANSI standards now have a "nutrition facts" sort of panel to make it easier for consumers to compare side by side.

InfinitusEquitas said:

Read up: http://www.streamlight.com/Documents/ansi/ansi-pres.pdf

I think they screwed up a bit in creating the standard, and not adding a qualifier for the diameter of the area illuminated at half, and maximum distance, as well as the relative lux numbers.

Click to expand...

I was confused too, but I think this information is still attainable using the candela value, light's head diameter, and some maths that are too fancy for my blockhead. Curious if THEY take that into account when calculating beam distance.

I had to google for this, but apparently, the difference between lux and candela is
Lux is measured in lumens per square meter AT some distance
Cd is measured in lumens per steridian.

What confuses me is that if they use the cd value in the inverse square calculation, aren't they assuming, then, that the flashlight head is a point source? Or are they then assuming that the originating point is some distance behind the flashlight?

I also like that a lot of bulbs lately, include a CRI, and temperature rating. Pretty interesting to see that most of the clf, and led bulbs out there are only 80 CRI.

BShanahan14rulz said:

What confuses me is that if they use the cd value in the inverse square calculation, aren't they assuming, then, that the flashlight head is a point source? Or are they then assuming that the originating point is some distance behind the flashlight?

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That's a very interesting question. My guess is none, or few hobbyists account for that, and use the flashlight itself as the origin point.

For manufacturers though, it should be very easy to account for the difference.

I think it might be time for us to buy some of the flashlight people on other forums about this

Received the MX25L3vn, and K50vn.

Unfortunately the MX25L3vn is not dedomed, so will need to go back for that.

Overall it seems to be a more thought out design in stock form, vs the very similar SX25L3.

The K50vn is a big and pleasant surprise. In terms of quality from supbeam, it's the best showing yet. It also carries over the interface from the K40/TN31/TN32/TN35 lights, and with that, might well become my new favorite light. Now if only the sun would hurry up and go over the horizon.

What are your thoughts on the k40 vs. k50? I haven't looked at the specs side by side yet, but wondering what you get for the price difference in price between the two. The K50 looks like it would throw noticeably better than k40, but curious if you feel that it sacrifices any spill or if it is still as spilly as k40

From what Bing has said the k50, even stock, out performs the k40 in every way. More throw with slightly more spill but down side is larger

The K40, and K50 have exactly the same UI.

Aesthetically, imo, the K40 is more pleasing, in terms of design. The head of the K40 is much smaller, both in terms of width and depth, on the K50 it looks somewhat disproportionate. The K40 also has a better (imo) handle design. Obviously the K40 also has a smaller battery tune, so it feels somewhat better in the hand.

The angle of the reflector appears to be the same, so I expect in terms of spill, you will have a bit less with the K50, but not much.

The K50 has a smaller hotspot on the wall, from a few feet away.

Of course with it, you can also charge batteries in the light, which is a nice bonus.

Need to wait for it to get dark before I can say more, but so far I'm thoroughly impressed with it.

I thought Vinh said the K50 had a little more spill :thinking: I could be confusing it with the TK61vn or one of his 50 other lights he introduced during that month

EDIT: IMHO I dont think its worth it. Only nice thing is the ability to charge batteries. Other than that its too large IMO

Vs the K40, I think it's a very worthwhile option, if you're getting a new light.

If you already own one, it's a different story. It's a step up, not a leap up. The TK61vn would the way to go, to really see a difference.