OPSL Analysis

[White-Light]

Hi,

As I have some time on my hands and I was curious about white light at Awakenings seen using OPSL, I decided to run the figures through Chroma to see if they were still using Jenolas Whitelights as well as OPSL to make white.

Interesting result as it seems you don't need red to make white!!!!

It looks as if gold will do!!! Which completely turns conventional theory on its head!

Here's the analysis using 1 watt 532nm Green, 2.5 Watts 577nm Gold, 2.5 Watts 460nm True Blue (shows magenta in Chroma but Coherent says its true blue so think the gradient out slightly).



Interesting thing to all of this is that despite not needing red to make white only gold, you can still achieve magenta that looks like a fantastic deep red on the Awakening videos:



So it looks as if the limited colour pallette of mixed OPSL is actually better than the wider pallette of RGB and it achieves white without red!

[mixedgas]

[QUOTE=White-Light;94125]Hi,

As I have some time on my hands and I was curious about white light at Awakenings seen using OPSL, I decided to run the figures through Chroma to see if they were still using Jenolas Whitelights as well as OPSL to make white.

Interesting result as it seems you don't need red to make white!!!!
End quote:

YES, Your right!

Not so Well known, but known, effect from krypton lasers with the 482 and 568 lines. By PWMing them with a AO cell for each line, you could generate nearly the whole spectrum without encountering the red/yellow line competition problems in Krypton all lines lasers. Great for a dome, but did not work in corporate shows where raw power was needed, so a migration to mixed gas happened.


The effect was used in the early 80s by at least one company that I know of. I've seen it, and have set the laser up for kill red when working on a new krypton tube more then once.

Adding the 530 and 520 green lines of krypton really add to the spectrum.

If you want to see this, put a kill red medical optic on a krypton or mixedgas tube, I've done it a few times. The beam is a beautiful bluish white.

Even more beautiful is what you can do with a mix of just 568 or 575, 488 and , 647 The orange and violets are astounding. It even has a official name within ILDA circles, Nuclear Flamingo Magenta.

This is why many of us loved dome abstracts, you just cannot get that range of colors, with just RGB.

Steve

[Lightning Productions]

Did you ment awakenings in the Netherlands? The lasershow from Hugo LaserImage. I though he used the jenlas at this event. He also use opsl blue yellow to get some sort of white. You need to use realy good optics to get the beam nice alligned for a good white beam.

[mccarrot]

Did you ment awakenings in the Netherlands? The lasershow from Hugo LaserImage. I though he used the jenlas at this event. He also use opsl blue yellow to get some sort of white. You need to use realy good optics to get the beam nice alligned for a good white beam.

Possible but I doubt it, Awakenings is not that big event. Its legendary but not big.

The location is 2500m2 and got a capacity of aprox 3500 party people.
Using a 10W Q-switched Jenlas is little bit overkill in this location, even when split over 2 heads.

All recent party Hugo uses 4W RGB lasers (RGB lasersystems modules) or 5W OPSL green with the power turned down!

At partys like Qlimax with 20.000 people he does use the Jenlas.

[smogthemog]

How can anyone judge what is 'whitelight' when everyones eyes see's 'white' differently?

Chroma is as much use as the Pope's bollocks!

[danielbriggs]

Chroma is as much use as the Pope's bollocks!

Hear hear!
Best, and most correct, thing I've heard all week.

[tocket]

How can anyone judge what is 'whitelight' when everyones eyes see's 'white' differently?

Chroma is as much use as the Pope's bollocks!

Yes, our perception of color is individual, yet similar (unless you're colorblind). Color science would not exist if there were enormous differences between how people perceive color.

The discrepancies you see are likely largely dependent on fundamental errors in measurements on and design of the laser projectors.

In other words, if you think that Chroma is way off, you are probably doing something wrong.

[Jem]

I don't think anyone is really disputing that Chroma is 'way off', in fact it's a brilliant piece of software and has its uses.

However, I do think people (think hobbyists here) are becoming obsesssed with obtaining a 'perfect' white balance (whatever that is). I've seen many projectors, all with varying powers of lasers. Some of them produce the most visually stunning whites that if you ran the figures through the software shouldn't look as good as they actually do.

Chroma is maybe a good place to start, somewhere to 'get an idea' of the wavelength and strength of the lasers needed. But beyond that, well, for us hobbyists anyway, I just say go for it and then judge the colours for yourself once your projector's built.

Hell, we're getting as bad as HiFi enthusiasts here. you know the ones I mean... Those who turn their speaker cables round from time to time so the electrons(?) don't get used to flowing in the same direction

Just my £0.02's worth

Jem

[smogthemog]

What I am saying is - Chroma will tell you what actual white is and what exact amounts of RGB you need to get that white.
In reality, what our eyes see as white is not the same unless you have perfect colour vision. 8.5 percent of humans have some degree of colour blindness, including me, and what I see as white will be different to what maybe you see as white.

It's an individual thing as to how you or I set up our projectors to get what we perceive as being white.

I used to set up old CRT TV's, back in the day when I was a field service engineer and used to have to set the grey scale of a telly slightly over on the R&G because I am R&G colourblind. If I set up a telly without this compensation then the grey would look to most as being yellow in hue because I was trying to compensate for my lack of being able to see R&G properly.

The shade of white is an individual thing.

I run around 300mW of 473, 900mW of 635 and 700mW of 532 and to me - AND OTHERS - this gives a good, bright white!

How do you work that one out?

PS - The output from a whitelight GAS laser look blue'ish to me.

[Xytrell]

Hell, we're getting as bad as HiFi enthusiasts here. you know the ones I mean... Those who turn their speaker cables round from time to time so the electrons(?) don't get used to flowing in the same direction

But... audio signals are AC