Deciding on green power and software...

[GooeyGus]

I'm now finally in the position to start planning out all the components I'm going to buy to finish my scanner (i'll probably buy it all at once at the beginning of the year).

I've been debating on how much green I should use. I'm basing the powers of my green and red lasers off of how much blue I have, which is about 110mW of 473.

To achieve good color match, I'd probably only need around 75mW or so, BUT I was also thinking that I may want to do some 'green only' shows where I could just crank up the green and turn the other channels off. I was thinking about using around 300mW of green.

I guess what I'm not familiar with is the software side of things. I don't know if I'll be able to dump a bunch of money in for a pango setup, but I'll probably have around $500 or so for a decent dac with software. With this budget, what software/dac can I get that will allow me to tone down the green when doing RGB but allow it to go all the way up while running by itself?

[Anthony]

Turning down 300mw of green to match your 110mw blue isn't a smart thing to do if you want to have nice fading/smooth grandient colors.

Affordable Dpss lasers arent really liniar so cutting down 70% of the power give's you al sorts of problems.

The pango ld2k software can handle it...but the laser is the weak factor.
I know Rob (stanwax) laserwave Uk is currently working on a circuit that balances lasers and give you maximum power at single color projection.
This without the need for 1500$ pangolin software. (pango give you mutch more that just good colors.. but thats another topic)

[Pitts]

Given the technical issues with DPSS modules as outlined by Anthoney there is something one should consider.

In this game enough is never enough !!! (unless you lie to yourself)

If you troll through the various price lists you start to notice for each colour there is a "sweet" spot to buy at..

eg..... IF say 100mw cost $300.00
say 200mw cost $350.00
say 300mw cost $400.00
say 400mw cost $1200.00
Guess the sweet spot is about the 300mw job...
This seems to occur for all colours (at different pricing)

By the way the linear modulation thing, which is real... varies a lot from brand to brand and model to model. I use a CNI 500mw green in my RGB and have no issues with "turning it down" using LD2000.. however of course another unit may well give issues.

Just some thoughts.. good luck.

pm me if you want any Pango' pricing..

Cheers

Ray
NZ

[buffo]

Your color calculations are correct. I have 100 mw of 473 in my projector, and I normally run my green at around 75 mw to balance it. (After all the optical losses, I end up pushing around 62 mw out the front end.)

I've run this projector with an 85 mw green, a 150 mw green (that is actually making more like 175), and a 250 mw green (which was doing nearly 285mw). I ended up settling on the 150 mw unit as the permanent green for this projector.

When I had the higher power unit installed, even though I had it turned down using the Pangolin color wizard, I noticed that it would initially come on brighter than it needed to be, and then dim back down to where it was supposed to be. This was a subtle effect, and you had to be looking for it to notice it.

The end result was that some patterns looked more green than they should have. I didn't notice it at first, but at SELEM 2008 it was very obvious that my projector was "greener" than the others. Still, when I went through the color balance adjustments, everything looked fine.

This problem is caused by non-linearities in the modulation response of the laser (jellybeaning), and is exceedingly common among DPSS lasers. The solution was to go back to the lower power (150 mw) green. Since I did that, I have not had any more color problems.

So I would caution you against buying *too* much extra green. A little extra is fine, because you can always select the "full power" color palette when you want that extra punch. But if you get too much, you may run into this non-linear effect that I did.

Adam

[Stuka]

......
So I would caution you against buying *too* much extra green. A little extra is fine, because you can always select the "full power" color palette when you want that extra punch. But if you get too much, you may run into this non-linear effect that I did.

Adam

Yep - I'm living proof of that, too!!
My 400mw of 532 is WAY too much for my 400mw 660 and 100mw 473, and when running a "balanced" color pallette I frequently run into "issues" with the 532. Hopefully, one of the color correction boards boards being developed by DZ or Stanwax will help "tame" the over-powered 532!!

Of course, when exact colors aren't necessarily an issue, such as for overhead beams, cranking everything up to full power DOES make for some cool, bright, greenish-white beams!

[daedal]

Just to throw a blind stab at this since I too have an extremely overpowered green, doesn't it seem to be a waste of money to kill the diode running it on low power?

I do understand that the diode will most probably be happier running at 75mW as opposed to 400mW (of output green), but how truly good is this in terms of diode life? The diode will degrade, regardless of power, the longer that it stays on. My assumption is that you might get, say, 2 times as much life out of it... That still doesn't justify the extra cost if you're buying it knowing what you're getting into... Please correct me if I'm wrong.

--DDL

[Things]

hey Daedal,, the reason he wants to get a higher powered green is if he wanted to do jusst a single colour, high powered beam show, so he has the power there if he needs it. I don't think he's worried about diode life, they all die eventually, nothing much you can do about it.

PS, for my projector, I have about 150mw> or so of green, and adding 600mw or so of 650 red.