Fenix TK11 brightness rating

[kyhunter1]

I recently purchased a Fenix TK11 and love it. It is brighter than any led I have previously tried hands down. It is rated at 225 lumens on high. I think this is overrated. I know it is over a 100 lumens for sure, but really not a 200+ lumen light. Has anyone ever tested the lumen value on this light against the manufacturers rating?

 

[Patriot]

I recently purchased a Fenix TK11 and love it. It is brighter than any led I have previously tried hands down. It is rated at 225 lumens on high. I think this is overrated. I know it is over a 100 lumens for sure, but really not a 200+ lumen light. Has anyone ever tested the lumen value on this light against the manufacturers rating?

:welcome:

It's probably a true 200-225 lumens at the emitter but not out the front of the light. Actual lumens out the front, after being reflected and having gone through the lens are closer to 150.

 

[kyhunter1]

150 lumens is more of what I thought it would be.

 

[rockz4532]

wow i thought fenix was preey acurate at lumen readings. another example of exaggeration...

 

[jake25]

I highly doubt its 150 out the front. I would say closer to 180-190.

 

[applevision]

150 lumens is more of what I thought it would be.

Welcome to CPF!

I love the TK11 as well.

There is a *lot* of discussion on actual lumens vs. manufacturer-reported lumens around here, with some companies known to exaggerate a bit and others to actually underestimate a bit... You may know this if you have been lurking for awhile, of course. I agree with the sentiment that it would be so nice to have a standardized, independently verified "out the front" lumen report on each light. Until that day, however, beamshots will continue to be as good as gold!

 

[Gunner12]

Fenix rated at the LED lumen light for most of their ratings, which is lower then out the front since light is loss in the reflector and window, like most other companies. It seems like the T series is closer to or at out the front lumen.

What light are you comparing the TK11 to? Some companies like Surefire, Arc, and Novatac rate out the front lumen. Surefire under rates their light so 60 lumen for Surefire might be 100 lumen at the source for another company.

Also remember that our eyes aren't that good at judging output. It takes 4x the output for light 1 to seem 2x as bright as light 2, presuming that they both have the same beam pattern. The beam pattern and tint can also make a dimmer light seem brighter.

 

[I came to the light...]

There is too much to be said, and too little to be gained from it, about manufacturer rated lumens. Honestly, they mean nothing. Wait until you see some sort of comparison, like lux numbers, ceiling/lightbox bounce numbers, or beamshots.

The only consistency I have found in terms of exaggerations are that cheaper lights generally claim the same output while they are not as bright. However, even that is not perfectly consistent, with exceptions on both sides.

 

[MrGman]

I recently purchased a Fenix TK11 and love it. It is brighter than any led I have previously tried hands down. It is rated at 225 lumens on high. I think this is overrated. I know it is over a 100 lumens for sure, but really not a 200+ lumen light. Has anyone ever tested the lumen value on this light against the manufacturers rating?

I have the original T1 which is supposed to be the same driver, LED, but with the OP reflector. The glass window in front is AR coated on both sides. I have measured mine in an integration sphere at work several times and I have gotten readings between 230 and 225 real lumens out the front on the T1. The TK10 and TK11 should be no worse. With the smooth reflector the TK11 should actually be a little better. I have measured a dozen different LED lights. I know the Solarforce R2 pills in the Sure Fire host put out 220 lumens, the Malkoff M60 is a 215 to 220 lumen output. The Malkoff M60F is a 202 lumen output. The Integration Sphere gets calibration check every year. These are real through the glass numbers. It is what it is. I have published my various results many times.

Some companies publish the truth of what their actual flashlight product puts out the front within a very reasonable percentage, some give raw lumens of the LED source under perfect conditions and not from their flashlight, so what vendor's say will vary, but speculation by naysayers is meaningless.

 

[Art Vandelay]

Most flashlight companies just look up how many lumens the LED manufacturer says the LED will produce at whatever power level will be used. They have charts where you can look up lumens at 750 mA, 1000 mA and so on.

You can't compare those numbers to the lumen numbers given by Surefire. Surefire is one of the handful of flashlight companies that measure and make public the out the front numbers. It's expensive, and your numbers look smaller than the companies that give the emitter lumens. Plus, people are very likely to doubt your numbers. Just look how people made negative comments about Surefire (with no proof at all) when Surefire changed the lumen numbers of its LEDs to make them more accurate.

 

[richardcpf]

So how does Fenix 225 lumens compare to the NDX 200 lumens and the eagletac 295lms?

 

[Axion]

Light-reviews.com has lux readings for a bunch of lights. I see nothing to suggest that fenix lights are over rated. With an 11,000 lux spot and big wide 200 lux spill it does better then most ~225 lumen lights.

 

[daveman]

I have the original T1 which is supposed to be the same driver, LED, but with the OP reflector. The glass window in front is AR coated on both sides. I have measured mine in an integration sphere at work several times and I have gotten readings between 230 and 225 real lumens out the front on the T1. The TK10 and TK11 should be no worse. With the smooth reflector the TK11 should actually be a little better. I have measured a dozen different LED lights. I know the Solarforce R2 pills in the Sure Fire host put out 220 lumens, the Malkoff M60 is a 215 to 220 lumen output. The Malkoff M60F is a 202 lumen output. The Integration Sphere gets calibration check every year. These are real through the glass numbers. It is what it is. I have published my various results many times.

Some companies publish the truth of what their actual flashlight product puts out the front within a very reasonable percentage, some give raw lumens of the LED source under perfect conditions and not from their flashlight, so what vendor's say will vary, but speculation by naysayers is meaningless.

I guess it's settled then, case closed.

 

[Patriot]

wow i thought fenix was preey acurate at lumen readings. another example of exaggeration...

It's not really an exaggeration but more of a difference in measurement.

MrGman
I have the original T1 which is supposed to be the same driver, LED, but with the OP reflector. The glass window in front is AR coated on both sides. I have measured mine in an integration sphere at work several times and I have gotten readings between 230 and 225 real lumens out the front on the T1. The TK10 and TK11 should be no worse. With the smooth reflector the TK11 should actually be a little better. I have measured a dozen different LED lights. I know the Solarforce R2 pills in the Sure Fire host put out 220 lumens, the Malkoff M60 is a 215 to 220 lumen output. The Malkoff M60F is a 202 lumen output. The Integration Sphere gets calibration check every year. These are real through the glass numbers. It is what it is. I have published my various results many times.

If it's producing 220 lumens out the front then it would have to produce around 280 lumens at the LED which isn't happening in this case since amp draw is a measured value. We already know from manufacturer's data that the LED isn't emitting that amount of light. Nickel or Rhodium coatings on consumer products like the Fenix lights simply aren't that efficient at redirecting light and are only about 75-80% efficient. Add to that a percentage point or two lost through the best optically coated flashlight lens and it's not going to be more than 75% efficient at getting lumens out the front. 75% would be a best case scenario. If you have access to a integrating sphere then I don't question that you could be seeing the numbers that you're seeing but the IS has to be precisely specific to the device being measured too. For example a person wouldn't test an HID spotlight in the same IS used to test a pocketlight or visa versa.

This subject has been discussed many times in the past with the same questions coming up over and over again. The answers aren't going to change since there have been no extraordinary advancements in reflector coatings. The most promising development to make its way into some resent designs are T.I.R. optics which significantly change the playing field with regards to light transmission characteristics. These are capable of much high efficiency but obviously doesn't apply in the case of the Fenix.


Here is another thread discussing a very similar topic:
http://www.candlepowerforums.com/vb/showthread.php?t=182999

 

[kyhunter1]

Thanks for the insight guys.

 

[MrGman]

It's not really an exaggeration but more of a difference in measurement.

If it's producing 220 lumens out the front then it would have to produce around 280 lumens at the LED which isn't happening in this case since amp draw is a measured value. We already know from manufacturer's data that the LED isn't emitting that amount of light. Nickel or Rhodium coatings on consumer products like the Fenix lights simply aren't that efficient at redirecting light and are only about 75-80% efficient. Add to that a percentage point or two lost through the best optically coated flashlight lens and it's not going to be more than 75% efficient at getting lumens out the front. 75% would be a best case scenario. If you have access to a integrating sphere then I don't question that you could be seeing the numbers that you're seeing but the IS has to be precisely specific to the device being measured too. For example a person wouldn't test an HID spotlight in the same IS used to test a pocketlight or visa versa.

This subject has been discussed many times in the past with the same questions coming up over and over again. The answers aren't going to change since there have been no extraordinary advancements in reflector coatings. The most promising development to make its way into some resent designs are T.I.R. optics which significantly change the playing field with regards to light transmission characteristics. These are capable of much high efficiency but obviously doesn't apply in the case of the Fenix.


Here is another thread discussing a very similar topic:
http://www.candlepowerforums.com/vb/showthread.php?t=182999

That other thread is all talk. Pay attention. I measured a Fenix T1 which has the exact same driver, LED and reflector as the TK10 and only differs from the TK11 in that it has the smooth reflector in a real $10,000 Integration Sphere/Lumens Meter system, calibrated yearly. Its actual measured lumens out the front glass, since I have never taken it apart and never will, is 225 lumens, I have gotten a peak reading of 230 lumens. Your reverse logic of why it can't be what it actually is because the emitter lumens would have to be 280 is meaningless. It measures 225 lumens.

As I said to another non believer, I have calibration stickers what have you got!

 

[Marduke]

As I said to another non believer, I have calibration stickers what have you got!

Denial.... :tinfoil:

 

[Jarl]

If it's producing 220 lumens out the front then it would have to produce around 280 lumens at the LED which isn't happening in this case since amp draw is a measured value.

Don't know how they did it, don't really care. It has been approximated to be 225 OTF lumens by several guys doing the old bathroom ceiling/luxmeter trick, as well as tested in a calibrated IS.

 

[Patriot]

That other thread is all talk. Pay attention. I measured a Fenix T1 which has the exact same driver, LED and reflector as the TK10 and only differs from the TK11 in that it has the smooth reflector in a real $10,000 Integration Sphere/Lumens Meter system, calibrated yearly. Its actual measured lumens out the front glass, since I have never taken it apart and never will, is 225 lumens, I have gotten a peak reading of 230 lumens. Your reverse logic of why it can't be what it actually is because the emitter lumens would have to be 280 is meaningless. It measures 225 lumens.

As I said to another non believer, I have calibration stickers what have you got!

I've got these...special just for you

I'll concede the I.S. is accurate, that your using it correctly and that it's indicating the figure you say that it is but if that figure is indeed 225 lumens then something else is missing in the equation. just out of curiosity what was the lumen reading from the Integrating Sphere after 60, 90 or 120 minutes of run-time?

It's not that you're giving us a wrong output number...at this point I'm only questioning it's usefulness. We're not getting any additional information or asking if the manufacturer should even make that claim in the first place. If the TK11 can't maintain the output for it's stated regulated run-time then these facts should be discussed.

The TK11 is stated to produce 225 lumens presumably out the front, for 2.7 hours with an 18650. Since all of these lights use the same batteries and the same emitters, one of them isn't going to magically stand out as having output or efficiency far superior to anything else available. For 225 lumens to come out of the front of a nickel reflector and multi-coat optic it's going to require about 280 lumens at the emitter which requires about 1.25A. If the light is indeed pushing 280+ emitter lumens then it's not going to be able to maintain that level of output for long. If this is the case then it does put into question the TK11's claim of 225 lumens since it doesn't mean much if it can't maintain than output for a reasonable amount of time.

Although it's interesting to read about a test that someone did on a $10,000 I.S. it actually provides us with less meaningful data than someone with a light meter, timer and graph program. I think the problem that I have with claimed output figures is that the manufacturers don't tell us how they arrived at the figures. For example if a light has been measured at 225 peak lumens, then perhaps it should be stated that they're peak lumens. If a manufacturer as taken the time to measure a light's output throughout its runtime, then averaged the output figure, then I wish that they'd state that figure as averaged lumens.

 

[Marduke]

I've got these...special just for you



I'll conceed the I.S. is accurate, that your using it correctly and that it's indicating the figure you say that it is but if that figure is indeed 225 lumens then something else is missing in the equation. just out of curiosity what was the lumen reading from the Integrating Sphere after 60, 90 or 120 minutes of run-time?

It's not that you're giving us a wrong output number...at this point I'm only questioning it's usefulness. We're not getting any additional information or asking if the manufacturer should even make that claim in the first place. If the TK11 can't maintain the output for it's stated regulated run-time then these facts should be discussed.

The TK11 is stated to produce 225 lumens presumably out the front, for 2.7 hours with an 18650. Since all of these lights use the same batteries and the same emitters, one of them isn't going to magically stand out as having output or efficiency far superior to anything else available. For 225 lumens to come out of the front of a nickel reflector and multi-coat optic it's going to require about 280 lumens at the emitter which requires about 1.25A. If the light is indeed pushing 280+ emitter lumens then it's not going to be able to maintain that level of output for long. If this is the case then it does put into question the TK11's claim of 225 lumens since it doesn't mean much if it can't maintain than output for a reasonable amount of time.

Although it's interesting to read about a test that someone did on a $10,000 I.S. it actually provides us with less meaningful data than someone with a light meter, timer and graph program. I think the problem that I have with claimed output figures is that the manufacturers don't tell us how they arrived at the figures. For example if a light has been measured at 225 peak lumens, then perhaps it should be stated that they're peak lumens. If a manufacturer as taken the time to measure a light's output througout it's runtime and then averaged the output figure, then I wish that they'd state that figure as averaged lumens.

There are plenty of existing runtime graphs for the T1. Guess what they show?? Table top flat regulation..... for a CONSTANT, AVERAGE output of 225 TORCH lumens, with a peak at 230.

http://www.candlepowerforums.com/vb/showthread.php?t=183623&highlight=Fenix

The rest of CPF has long suspected the T series was torch lumens, so this is not really surprising news. Where have you been??