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Brightness by wavelength?

GamerBR

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Re: Apparent brightness by wavelength?

daguin said:
[quote author=GamerBR link=1213558310/0#10 date=1213561591]Anyway the graph seems to confirm what I read,that green lasers appears 8 times brighter than red lasers at the same power.

You "see" that in this graph?


:eek: :-? ::)

Peace,
dave[/quote]
Of course it's not precise,but it's close to that
:D
 

diachi

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Re: Apparent brightness by wavelength?

It just depends on the viewer, my friends see my greenies alot brighter than I do .

Diachi
 
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everyones eyes are structured slightly differently, so it's not lab-accurate...but I'd say it's safe to assume that graph is an average for layman informational purposes.

It's interesting. Good topic
 

Switch

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Re: Apparent brightness by wavelength?

GamerBR said:
[quote author=Switch link=1213558310/12#15 date=1213562595]Well , yea.....(?)

:-/ :-/
What you marked as 650nm is 532nm and what you marked as 532nm is 650nm :-/[/quote]

Yes, i did.It's called a mistake , and we all do it. ;D

It's late here. ::)
 

Paul0759

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Sorry to bring up an old thread but i thought id search rather than ask something that may have been asked before.

So... that graph is showing somewhere around 555nm to appear as the most brightest wavelength to the human eye?
Im just wondering if that being the case a 10mw 555nm could appear as 12% brighter than a 532nm, pretty interesting stuff i must say.



So that yellow should appear as bright to us as the 532's.

Again, sorry to bring up and old thread.

:)
 
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Synchros

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That graph directly above is highlighting roughly 523nm and 578nm. In bright conditions 532 is still brighter than 589 but not by much. But, accordingly, the yellow lines are way dimmer by comparison in dark conditions. It seems hard to believe but it's apparently true.
 

rhd

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Does anyone know of a trusted member in Canada with the ability to test wavelength?

I have a 445 that appeared to skew higher, to the extent that what caught my attention was a visible difference in colour next to other 445s. I tested on a diffraction grating, and it is indeed skewing higher. I'd love to know what this diode is actually outputting.
 

Synchros

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I have a 445 that appeared to skew higher, to the extent that what caught my attention was a visible difference in colour next to other 445s. I tested on a diffraction grating, and it is indeed skewing higher. I'd love to know what this diode is actually outputting.
That's interesting. Is there fluctuation in current that would be causing that? If you had to ball park the wavelength what would you guess? 460ish? My curiosity is piqued.
 

lasersbee

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I have two ~1W 445nm Lasers that I took outside in the
Fog early one dark morning...
when I turned them on at the same time side by side...
one was a nice Blue and the other looked Violet. It almost
(but not quite) looked like a PHR 405nm...

I'm going to need a spectrometer soon...:whistle:


can you PLEASE remove that retarted picture lol !!!! i HATE it so much
What retarded picture are you referring to...:thinking:


Jerry
 
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Synchros

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I think he's referring to my attractive avatar! LOL!! :D Perhaps he'd prefer this one!



Moowah hah aah....:eg:

I'll get around to changing it soon. I think I did something with a new laser that made me feel like my avatar looks! I need to "smart-ify" my avatar, me thinks. :D

Is current responsible then for wavelength shift? Or would it rather be more directly heat related?
 
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InfinitusEquitas

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I have one 445nm, that definitely looks different from all my other 445's. More a brighter blue.

If there is anyone in NYC area who has a spectrometer, I would love to get it tested:p

@Synchros - Don't you even think of making that crazy exercise nut your new avatar. Just got used to ignoring the current one.
 

rhd

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That's interesting. Is there fluctuation in current that would be causing that? If you had to ball park the wavelength what would you guess? 460ish? My curiosity is piqued.
Well, fluctuations in current wouldn't do that. Potentially a different level of current (different power output) could trick my eyes into thinking I was seeing different colours when I was really seeing the same wavelength.

Here's where it gets weird. I thought about ^ theory, and grabbed my LPM to test it. I thought that perhaps the laser that appeared lower in wavelength might have just been a 445 that was outputting less power (and thus tricking my eyes into seeing less intense blue and thinking it was a less-blue wavelength).

When I measured the output power, the 445 that skews visibly more towards violet was a 1.7W laser. The 445 the skews more towards higher wavelengths was only 1.3W. The 1.3 appears brighter, and it certainly looks more blue.

In a blind test, I'd be able to tell the beams apart 100 times out of 100, it's that obvious. It might even be a substantial enough colour difference that I could pick it up on camera.
 

Synchros

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You should definitely try photographing that. It may well show.

Perhaps the higher current drawn by the 1.7W, for whatever oddball reason, is causing higher energy output wavelength then. It would make more sense than shifting to the longer, lower energy wavelengths.

Do you know if both diodes are manufactured by the same producer? If so it would have to have something to do with current as the gain mediums would be of the same exact recipe for what it's worth. If they're different maybe one has a little Big Mac sauce mixed in. :D
 




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