Szemhazai
Enlightened
How many lumen's you need using 18* optics to see this kind of effect on your own eyes ??
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[Pool] How much lumens you can see ?
- Thread starter Szemhazai
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It's impossible to say without knowing the camera exposure. For example that could be an Arc AAA with 5.5 lumens shot with a long exposure. Or it could be a 10,000 lumen monster with a short exposure.
Edit: your bike light comparison is good though since it's all shot with the same exposure.
Edit: your bike light comparison is good though since it's all shot with the same exposure.
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diff_lock2
Newly Enlightened
He says if you saw that with your own eyes. I would have to say easily over 1000lm, but then again white leds are really intense, they really cook your eyes.
Similar situation though; your eyes adapt to different light levels in the same way as a camera changes it's exposure. I just don't think it's a very scientific question.
diff_lock2
Newly Enlightened
Well... i don't think your night vision is that good, if i lit up the forest with 20lm your eyes wont adjust to reproduce the image above.
I understand what you are saying but if your saying that we can see that (pic) much light with variable lumen levels why run more power full lights?
How about this: What do you think is the minimum lm output you would think is needed for you to see what is shown in the picture?
I understand what you are saying but if your saying that we can see that (pic) much light with variable lumen levels why run more power full lights?
How about this: What do you think is the minimum lm output you would think is needed for you to see what is shown in the picture?
tonycollinet
Newly Enlightened
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- Oct 15, 2007
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No it's not scientific - but not all questions need to be. Go out into the dark with a bright hand torch, stand in front of your car, and point it forward. Now switch on the car headlamps. Which is brighter? Roughly (to your perception) how much brighter - 2 times, 3 times, 10 times. This is the sort of estimate the OP is looking for.
I currently use 3xluxeon III stars, run at 1A, which should put out around 80lm each - total 240lm.
I estimate that what I "see" is a bit less than half as bright as the picture, so by that estimate you are going to need 500lm+
co-incidentally that is exactly what I will aim at for my next light, hopefully based on a triple rebel star - when I can get one together with suitable optics.
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Yes, but that would be a relative measurement and only useful for a direct comparison. It's just not possible to perform an accurate comparison between a flashlight and a computer monitor.
It's true that a 20lm light would not appear this bright but this is because of the minimum sensitivity of the eye. I think the visual effect of the picture could be achieved with anything from 200lm to 2000lm depending on how well adapted your night vision happened to be. (Remember the eye's response is logarithmic.)
One thing I do agree on however, is that this is a pretty dumb advert. "Max brightness: 90 lux" - It's meaningless to quote an intensity without also quoting the distance.
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Szemhazai
Enlightened
it looks that I have to explain something - the whole idea of this poll was to confront "advertisement vs reality". The lamp that at it best have 220 lumens output versus photo on which you can see effect that can be achieved with at least 600 lumens. 
monkeyboy is claiming that ayes can adopt, but I must undermine that - during ride with strong light your eyes can't adopt so well. I.E. when you will be passing the tree, it will be so bright that your ayes will set off accommodation for next 15 minutes. Moreover, almost 50% of population has their "night vision" defective in case of abusing fluorescent light and some medical issues.
