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ArcticMyst Security by Avery

Ratio - R:G:B

VW

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I noticed a lot of people are asking these questions, and I have a few questions on this also, so I thought I might as well create a thread dedicated to the subject.

So what are good ratio's between the three wavelengths?  In the future I plan to get a 50mW 473nm labby and will afterwards get R+G to fit around that.  I noticed a lot of people have a lot more R+G than B, I understand you need to have a lot of red to get a good tone, but why so much green over blue?  ANy info and actual ratio's is much apreciated...
 





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Because green is cheap. To have a true, perfect white balance you need the most red, but you also need a lot of blue, and the least green. However, green is so cheap and bright, you can get a MUCH brighter beam per $ by using more green, and really, in a club with a lasershow, how many people are gunna stop to think "huh, that white beam of light looks a little green tinted, I should be angry that the operator is cheaping out on his blue component emitter"

Good white balance depends on a lot of things. Just using solid state alone (IE< if you arent using gas lasers), there are vast differences between using 473nm vs 457nm, and using 660nm single mode versus, 660nm or 635nm multimode, or 671nm DPSS. All bring their own set of pros and cons to the mix. Not to mention that the proportions change based on power. 4 red : 2 blue : 1 green is a commonly quoted ratio, but its a very very rough estimate. Perhaps that ratio may work with one mix of wavelengths at a certain power, but even just increasing the total power of your setup can shift the ratio. So its a tricky subject eh?

Normally if you're buying the individual modules from a company, you can explain the situation to them and they will help suggest a white balance ratio for your situation.
 
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For just a general rule of thumb the ratio is 1:2:4 of green blue and red, but this is not solid and as pseudo said depends a lot on your individual lasers - so the output will need to be tweaked to get a good white balance
 
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is 1/2/4 the Mw ratio?
like
100green/200blue/400red
30green/60blue/120red

etc...
 
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in a club with a lasershow, how many people are gunna stop to think "huh, that white beam of light looks a little green tinted, I should be angry that the operator is cheaping out on his blue component emitter"

maybe i'd be the ONLY one on the club, but I WOULD :p
 

FokoF

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Also you will need analogue modulation to get the perfect white balance....
 
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the power of each laser does not matter, end of.

what does matter is analogue modulation.
 
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andy_con said:
the power of each laser does not matter, end of.

what does matter is analogue modulation.

Well, you really wanna get as close as possible from the start though - analog modulation is a given in any case if you're making an RGB for lasershows. I mean, sure you could could a 500mW red, 10W green and 100W blue and still get the right white balance from severly underpowering the green and blue but... well you see what I'm getting at here.

The better your ratio from the beginning, the more money you save. If you still need some corrections, you can take care of that by shrinking the range you modulate at (I'm guessing that would also result in your range being less linear, so its still better to try to get it as close as possible from the start).
 
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indeed i agree but with a nice big green in there you can turn it down for rgb shows or turn it on full for just awesome green shows.

im running 500mw green, 300mw red and 100mw blue. i turn the green down to match then turn it up for just green shows
 
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thats not a bad idea.. .. i will probably upgrade my green later.. when (and if) i get my blue..
 




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