Yes, they are perceived the same way. The dB is just a way to express things that have Huge dynamic ranges like light and sound perception. No need to obscure things with photopic and scotopic vision.
NiteCore Lumens Rating
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Yes, they are perceived the same way. The dB is just a way to express things that have Huge dynamic ranges like light and sound perception. No need to obscure things with photopic and scotopic vision.
Decibells are just a logarithmic level scale. They don't really have a physical dimension or meaning. And there IS a need to "obscure" things, as you've put it, because lumens (percieved flux) are tied to watts (radiant flux) via a human eye's wavelength characteristic.
Things aren't as simple as they (might) seem.
Things aren't as simple as they (might) seem.
WildChild
Flashlight Enthusiast
To my naked eye, doing a ceiling bounce test, I found the D10 on NiMH to be about as bright as my SureFire L1 (65 SF torch lumens). With many swap between the two, I cannot tell if one is brighter than the other. Next to the E2DL (120 SF torch lumens), the D10 is way dimmer. chevrofreak made runtime test on these lights. His test approximated the D10 to be around 95-100 lumens on NiMH.
http://www.chevrofreak.com/Nitecore SmartPD D10 - max.png
http://www.chevrofreak.com/Nitecore SmartPD D10 - max.png
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This is quite correct I do not mean to use my photos quantitatively -
they are there just for a "look-see" - more for qualitative usage. So you are correct there.
However when one can see a difference in brightness - a photo will show a difference too - whether it is measurable from the photo I can't say - when I can see a difference side-by-side - a side-by-side beamshot (where both beams are in the same photo) the difference shows up.
That is all I was trying to illustrate - the Extreme on primary CR123 is rated by NiteCore as 190 lumens - while the D10, NDI and EX10 were all rated at 130 lumens regardless of whether they were on primary or Li-Ion -
in real-life look-see I could not see any real difference between the Extreme and those other flashlights - and I used my side-by-side beamshots to illustrate that - of course there probably is some absolute measurable difference - but IMHO I doubt that it would be quite as much as a 60 lumens difference.
I apologize for my poor choice of the word "huge" -
but the simple fact is I can see little to no difference between the Extreme, EX10, D10 and NDI (on Li-Ion) -
whereas I can see a difference between the D10 (and/or NDI) when they were on NiMH and Li-Ion - so a difference is both noticable and capable of being shown in a photo.
So nitecore didn't "underrate" the output after all. It is around 100 lumens on NiMh and 110-120 on li-ion. Everybody was like "it's sooo bright, it's as bright as the P3D, it's 190 lumens AT LEAST".
Color removed/deSaturated versions -
Color/tint removed by desaturation -
I think one can see difference between these shots -
probably in the order of Fenix P3D-Q5 > EX10 = P3D-RB100 > P2D-Q5
Ratings given by Fenix are (links to Fenix specs) -
P3D-Q5 = 215 lumens
P3D-RB100 = 200 lumens
P2D-Q5 = 180 lumens
Yet NiteCore's rating for the EX10 is 130 lumens....
Like it or not, that's the way things work.
1 W of radiant flux produces a certain number of lumens of luminous flux at a certain wavelength. And a completely different number of lumens at a different wavelength. It's more similar to weighted dB scales, really.
Also, the peak (and the link between watts and lumens) changes for scotopic vision, due to a different characteristic for the rod cells.
Edit: Just BTW, where did that bit about a 10 dB increase come from? Why would it take EXACTLY an order of magnitude (i.e. 10x the flux) for the eye to register a change in brightness? Whoever said eyes see things in bases of ten?
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Actually I trust lux numbers more than pictures and my eyes. If the P3D was estimated to be around 200 lumens, and the D10 about 115 lumens (after the initial drop) using the same method, then that's what it is. To the eye a 100% increase looks like maybe 25% but that still doesn't mean it's not a 100% increase. A 30-40% increase in output is bearly noticable in pictures, but it's still there.
another way would be to look at runtimes. If the Extreme is really putting out that much light, it should run quite significantly shorter then the Ex10. Remember that a slight decrease in output give a correspondingly larger increase in runtime
Crenshaw
Crenshaw
Tohuwabohu
Newly Enlightened
I took some readings with my primitive an not yet finished light box (raw values from my millivoltmeter, nothing nomalized or calibrated).
I don't have any primaries, I had to use rechargeables.
NiteCore Ex10 max. 1xRCR123 (manufacturer rated 130 Lumen): 1.42
Nitecore Extreme max. 1xRCR123 (manufacturer rated 190 Lumen): 1.85
for comparison:
JetBeam JET-II Pro IBS max. 1xRCR123 (manufacturer rated 225 Lumen): 2.00
JetBeam JET-III Pro IBS max. 1x18650 (manufacturer rated 225 Lumen): 2.33
Fenix L2D Q5 Turbo 2x AA NiMH (manufacturer rated 180 Lumen): 1.74
All measurements were taken 15 minutes after turning on the lights.
My Extreme is brighter than my EX10 when both are running on RCR123s.
The ratio 1.85/1.42 = 1.3 is not as high as expected form the manufacturer values 190/130 = 1.46.
But it sees to be very close to selfbuilts results when looking at his runtime graphs.
I think my EX10 is putting out a bit more than 130 Lumen and my Extreme a bit less than 190.
Some variation seems to be normal. Just look at my two JetBeams: same driver, very similar reflector, same manufacturer rating but very different results in my light box.
I don't have any primaries, I had to use rechargeables.
NiteCore Ex10 max. 1xRCR123 (manufacturer rated 130 Lumen): 1.42
Nitecore Extreme max. 1xRCR123 (manufacturer rated 190 Lumen): 1.85
for comparison:
JetBeam JET-II Pro IBS max. 1xRCR123 (manufacturer rated 225 Lumen): 2.00
JetBeam JET-III Pro IBS max. 1x18650 (manufacturer rated 225 Lumen): 2.33
Fenix L2D Q5 Turbo 2x AA NiMH (manufacturer rated 180 Lumen): 1.74
All measurements were taken 15 minutes after turning on the lights.
My Extreme is brighter than my EX10 when both are running on RCR123s.
The ratio 1.85/1.42 = 1.3 is not as high as expected form the manufacturer values 190/130 = 1.46.
But it sees to be very close to selfbuilts results when looking at his runtime graphs.
I think my EX10 is putting out a bit more than 130 Lumen and my Extreme a bit less than 190.
Some variation seems to be normal. Just look at my two JetBeams: same driver, very similar reflector, same manufacturer rating but very different results in my light box.
I don't have an extreme but I did measure the EX10 and NDI and they are both boost only. On RCR's, they are not running in regulation and are direct drive minus a diode drop. Keep this in mind when you do comparisons using RCR's. Because the light is out of regulation, Vf will cause your results to vary from light to light. The differences you measure (1.3 vs 1.46) can be attributed to the fact that there is about 10% difference from the bottom to the top of a bin, plus there is usually a measurement error which can account for another 5% or more.
Tohuwabohu
Newly Enlightened
That is the reason why I did wait 15 minutes after turning on the lights before taking the reading.
In the meanwhile I completed my first runtime measurements: My EX10 and my Extreme running on AW's protected RCR123's:
My Extreme is brighter and the EX10 has a longer runtime, just as it should be.
My apologies for beinging up another thread -
but from your own words in the thread Nitecore EX10 Circuit Discussion
Post #17
Post #19
Post #21
Therefore going from 130 lumens to 190 lumens which is a 46% boost in brightness should be discernable side-by-side - both visibly by eye, and by photo.
Here's a comparison -
they are similar - with perhaps the EX10 on primary CR123 a bit brighter?
The difference in color/tint makes the comparison a bit harder -
Color/tint removed by desaturation -
EX10 does look brighter to me than the P2D-Q5.
Note please I used primary CR123 for these for the reasons I gave as being more reliable and reproducible - and also without the obvious drop/sag in brightness as seen in runtime tests - both these CR123 are not new - and have been used for several minutes in other beamshot tests.
Here is a more real-world like comparison -
Color/tint removed by desaturation -
The NiteCore EX10 looks brighter (to me) than the Fenix P2D-Q5 (both again on primary CR123) -
Fenix P2D-Q5 is rated by Fenix at 180 lumens....
NiteCore EX10 is rated by Nitecore at 130 lumens
The difference between the P2D and the EX10 seems to be about the same as the difference in output between the EX10 and the P3D. Only when something is brighter than the EX10 it's "barely noticable in real use" but when the EX10 is brigher it's suddenly a "HUGE difference".
I've already apologize for the wrong use of the word "huge" -
I was thinking that 60 lumens of being not insignificant -
as others have pointed out 60 lumens in context of 130 lumens is a 46% increase - which is actually noticable - and not insignificant - but not "huge".
Besides that word was used in context of the difference between the 190 lumens rating of the NiteCore Extreme and 130 lumens rating of the EX10 - and not anything to do with a comparison with any Fenix lights.
Let's put this into context and take anything to do with the NiteCore out of the equation for now -
The difference between the P2D-Q5 (180 lumens) and the P3D-RB100 (200 lumens) is "only" 20 lumens or 11% -
yet we can both see the difference in the beamshots.
So surely one should be able to see an increase of 60 lumens from 130 lumens (eg: Extreme 190 lumens vs EX10 130 lumens).
If the Fenix P3D-RB100 was for some reason rated at 140 lumens (instead of its 200 lumens) a 60 lumens (42%) difference
- shouldn't we both question it?
it is possible that more light makes it out of P3D then the P2D, for some unknown factors pertaining to optical efficiency. I am however, quite sure that wile 180 lumens is claimed in the P2D, its reported to have less then that in Torch Lumens. In fact, even the P1D on max is suposedly brighter.
Crenshaw
