How do Lumens or Candelas influence the beam?

Hi,

I've been trying to choose a dependable torch and I came across to these two torches, Nitecore EA8 and TM26. While I was (and still am) trying to work out which one's better, I realised that EA8 had 900lumens, 60,000cd and had beam distance of 490m, where as the TM26 had a 43,000cd, beam distance of 415m, and a whopping 3500lumens.

Now, for my question, how come EA8 had more beam distance than TM26 even though TM26 had way more lumens? Is it beacuse of the candelas? And if it is the candelas, then what do lumens measure?


Thanks,

Immahooo.

In short: Lumens= overall light output, Candelas= intensity of light in a direction. (Lux is brightness- lumens per area IIRC).

To give an example- an incandescent household lightbulb might emit 900 lumens, but it has a relatively low intensity because the light is spread out everywhere. A laser pointer might have a very low lumen output, but those lumens are all concentrated into a small, intense, area giving the laser pointer a high cd measurement.

When I'm looking at lights with ANSI beam distances, I always just half the number to give me an idea of 'practical throw'. The ANSI measurement is distance to .25 lux (moonlight on a clear night). At 400m, I definitely can't see what's lit up by a patch of moonlight!

The TM26 gets it's intensity from brute power whereas the EA8 will be more traditional 'focused' flashlight beam. Which is better will be determined by your intended useage- the TM26 is a massive floodlight while the EA8 is a spotlight (relatively speaking).

It's not all about size (lumens), it's how you use it that counts (beam shape) :thumbsup:...

Thanks for the info, now I know which one to get.

gravelmonkey said:

t.

When I'm looking at lights with ANSI beam distances, I always just half the number to give me an idea of 'practical throw'.

Click to expand...

That's a really good rule of thumb. . Otherwise most people will be greatly disappointed!

My Fenix PD32UE claims 155 meters (508 ft) of throw. I live on a lot that is 150 ft x 300 ft. When I'm at the front of my lot, I can moderately illuminate my neighbors trees that are just on their side of the fence (~95 meters / 310 feet) beyond that the light fades pretty fast.

At half the "spec" distance, which would be 254 feet, things are still illuminated very nicely.

Here's a very nice explanation, just keep in mind that candela is the same as Lux, just a different unit like foot VS meter.

Easy to Understand Lumens Vs Lux Explanation