Laserium

[dsli_jon]

It doesn't really - it need something to match the tempo...

Hah, yes, well.. I should-have 'qualified' this post.. Those clips were *not* from a show-performance, nor segment of the 'real' Doors Laserium Sho.. here's the real goods: http://www.youtube.com/watch?v=K_nbtoSKdzo

..All I did was quickly-hobble together those 'Dream-FX' clips and audio, all in 'iMovie'... the audio editing was pretty-hackums, as were the vid-transitions.. Took maybe an hour or so whist-waiting for a render.. Nothing special / official, just meant to show-off the spellbinding 'inferno-lookin' fx.. Was quite-awersome in real-life..

j

[polishedball]

Hah, yes, well.. I should-have 'qualified' this post.. Those clips were *not* from a show-performance, nor segment of the 'real' Doors Laserium Sho.. here's the real goods: http://www.youtube.com/watch?v=K_nbtoSKdzo

..All I did was quickly-hobble together those 'Dream-FX' clips and audio, all in 'iMovie'... the audio editing was pretty-hackums, as were the vid-transitions.. Took maybe an hour or so whist-waiting for a render.. Nothing special / official, just meant to show-off the spellbinding 'inferno-lookin' fx.. Was quite-awersome in real-life..

j

Soon I will be able to turn in different effect gratings by color line. Can't wait esp after seeing this.

[TechJunkie]

Lumia is by far one of my favorite effects. I've already wasted money on glass that didnt work. The shower glass works, but gets repetitive. Any tips/links to producing, and buying the proper material? Or are these trade secrets?

Confratz by the way. I would love to do a tour like that. +1 on keeping the Lumia love alive.

[The_Doctor]

Lumia is by far one of my favorite effects. I've already wasted money on glass that didnt work. The shower glass works, but gets repetitive. Any tips/links to producing, and buying the proper material? Or are these trade secrets?

The wired glass that has a wire grid in it, is about 8mm thick, and has little bumps irregularly all over one side, is very good at large variations over a very small region. The question is how you move it. The effects can be very different based on translation of glass in 2D along its own plane, or rotation around some point. If you can come up with a hybrid motion that lets you choose, so much the better. A starting basis might be a gimbal and some model plane servo control. Some patterns can be so spectacular (humanoid phantoms, landscapes) that it is worth making an accurate mover that can be programmed to find precise orientations and positions again on demand, and move from one to another preset point at will. CNC type accuracy will be needed though. Not cheap probably.

[laserist]

Lumia is by far one of my favorite effects. I've already wasted money on glass that didnt work. The shower glass works, but gets repetitive. Any tips/links to producing, and buying the proper material? Or are these trade secrets?

Confratz by the way. I would love to do a tour like that. +1 on keeping the Lumia love alive.

Trade secrets are so 70's. 1st rule is the glass you "wasted money on" didn't - not work - you just haven't figured out how to use it yet. Great Lumia effects are sometimes singles element effects - of the 18 pure lumia effects currently in the projector I'm using three are singles - if count that one is actually a dimple tube, and the one that's actually a raster scan through effect. Take the singles and experiment with adding a dimple, or a diffraction grating, or a crystal, liquid crystal to fuzz the effect, or...

Lumia is about finding the perfect effect for that singular part of your show, so are the scanned effects, and if you find the perfect lumia or scan effect that will work for everything - and you use it for everything the audience will almost certainly never forgive you.

[swamidog]

use two wheels counter rotating at slightly different speeds.

see the thread: "swami makes a lumia"

Lumia is by far one of my favorite effects. I've already wasted money on glass that didnt work. The shower glass works, but gets repetitive. Any tips/links to producing, and buying the proper material? Or are these trade secrets?

Confratz by the way. I would love to do a tour like that. +1 on keeping the Lumia love alive.

[TechJunkie]

Thanks for the tips fellas. For some reason most of the glass I bought doesnt make a large effect. @20 feet the effect is maybe 6 inch wide. I'm running ~1W of 405, and 2Ws of 445, so I know the power is there. I picked the glass for its texture, and heavy imperfections. One pane even has small bumps of glass, and still small effect. For whatever reasons I'm not getting a good spread of light. I'm also using a 1/3 RPM motor, so its not a speed issue. I did find some swirled plastic material that makes amazing effects, but I cant use high power because it cuts the material.

Trust me, I shoot my laser through every new type of material I come across. Its not from lack of trying.

[The_Doctor]

Interesting. I forgot about something till you said that. The wired glass I experimented with (only by hand) would throw an image that varied widely for scale, depending on whether it hit a wire, a blob, some rift in the glass or whatever. Throw distance was about 9 feet with images ranging from about 2 to 6 feet, based on a vague sense of when distinct pattern gives way to general peripheral spill (the spill being a lot wider, but fainter too).

What I forgot was that focus makes a huge difference. Point focus of beam onto glass made wider and sharper patterns, collimated beams made softer forms. There's good reason to experiment with the sharpness of focus, likely optimal at about 0.5 to 1 mm wide, but also the closeness of the source will make a difference. For wide and sharp patterns you probably need to get the laser's lens to as little as 10mm from the glass, then focus it down to a 0.5mm spot, but that limits how much the glass surface's distance can vary. It's definitely worth using a motorised focusser though, the effect of continuously variable intensity of edges is good. Torture tubes won't allow this, but wheels and flat wired glass will. The reason I like the wired glass is the extremity of variation and clarity and detail of imaging, combined with the total lack of requirement to heat and shape the glass. A bit of cutting and edge grinding, at most..

[TechJunkie]

If I can grab a piece of wired glass I'll try it.

I had it focused to a pin point. Why would closeness come into play? I thought the focal point was the key. Either way the laser was within 2 inches of the glass. I dont like to get to close because I worry about the beam reflecting back into the laser.

[The_Doctor]

Why would closeness come into play?

Ray tracing... If the focus and glass surface are very close the divergence after focus is a lot wider. Hence wider pattern on the wall. Point taken about reflection back at the laser though. It's probably best with the wired glass to put the flattest side toward the laser to prevent a concave bit of surface focussing the light back too much on one bit of facet. Also, if the surface and focus are close, then the photons that hit the glass and go back can't be going back the way they came because the angles are so different. And unless most of them ended up going back the energy density won't be high enough to harm it.

I never killed a diode while messing with wired glass. Usually the diode will only die by retroreflection if the return is both strong and simple in its pattern, because it's basically extending the laser cavity when it does this (is why the energy density rockets and causes the facet to get disrupted). Collimated beams coming back of flat mirrors is the easiest way to accidentally do it because when knife-edging and PBS'ing collimated beams the conditions are much closer to risking this damage. But if you're using a bit of wired glass at very short focal range the greatest risk is accidentally finding a small curved pit on the bumpy surface whose curvature matches well with the focal length enough to return a lot of light, so in this case the flatter side will help reduce that risk. Curves on the inside of bumbs on the far side might be a risk too but less so, the glass has uneven properties that will diffuse it a lot more by the time it reaches that far.

Btw, when I mentioned a focus of about 0.5mm to 1mm wide on the surface, I meant it. I have tried a truly sharp pinpoint and it's actually fairly boring. Much better patterns come from bigger spots, up to around 3mm wide maybe. That;s because you get more of the glass (and wire surface curvature) involved in making the pattern.