Is it possible for TK12 R2 to put out 247 OTF ?

[dhouseng]

Based on what Light-reviews.com says, the Fenix TK12 R2 puts out 247 OTF lumens on turbo mode. As I know the Fenix TK12 is normally driven at 1.0A max. So, how did they get 247 OTF with a 1.0A driven R2 ? Are the lights measured at 1st second of turning it on?

Also from the actual lumen readings, the fenix T1 Q5 has 225 OTF lumens on turbo. How did fenix achieve these numbers ??

 

[kramer5150]

Depending on how its measured... YES its possible to get that high of a reading from the TK12-R2. If the meter is set to "insta-peak" mode, where the meter only displays the maximum lumens.

In the BC 10.5" sphere, his meter is far more sensitive than the human eye. It can measure Lumen output in the milli-second interval. Burst output like this is far too short for the human eye to observe, but the meter sees it and displays it.

I was playing around with it once and measured one of my Malkoffs at ~260L (or there-abouts)... using peak-burst mode. But we all know that for any observable time duration (1-3 minutes) its output is more in the ~220L range.

I suspect the majority of light manufacturers who do use spheres, measure light this way... so its not fair to point fingers only at Fenix. Its an easy way to pad your specs with a LOT more Lumens than is visually observable. FWIW, Surefire and Malkoff are 2 manufacturers off the top of my head who do not publish peak-burst Lumen specs.

Theres some detailed discussion on this in Garys Lumen sphere thread.

 

[bigchelis]

I been noticing that current XR-E R2's seem to put out alot more lumens then before or maybe its a combo of high current and great heatsinks. I have some XR-E R2 20mm boards from DX that I plan to put in Mag 2D's for NiMH C/D projects to prove or disprove this theory.

Nailbender XR-E R2 at 1.3A = 290 OTF (238 at 3 min).

The Malkoff M30 1.8A at tail = 300 OTF (256 at 4 min)

Then there is the Milky XR-E R2 extreme at 2A = 390 OTF (338 at 3 min)


In the past my 1D Mag XR-E R2's at 1.2~1.4A would put out less then 200 OTF lumens. I think Cree is selling XR-E R3, but just decided to call them R2's instead.

 

[dhouseng]

Thanks for the explanations.

Wow, 390 OTF from an R2, imagine putting this in the dereelight DBS!

 

[bigchelis]

Thanks for the explanations.

Wow, 390 OTF from an R2, imagine putting this in the dereelight DBS!

If you built a solid copper P60 pill with no-room for driver and screwed it in I bet it would net similar results. Now; where do we purchase that solid copper base?

 

[ebow86]

I don't have any measuring instruments but my conclusion is that Fenix's figures HAVE to be a bit exaggerated, either that or they likely measure at the emitter. For example, my TK10 is rated at 225 lumens and low mode at 60 lum, I can tell you without question that there is no possible way it outputting 60 lums on low and probably now 225 on high. My eyes just tell me it can't be. And the TK30 is very bright, but I seriously doubt it putting out 630 lumens, probably around 500 to 550. Not a post to bash on fenix, I just believe their lumens rating can't be taken as fact.