Propagating Rainbow Effect?

[White-Light]

I think the colour effect can possibly be done but we had a discussion on the chopper effect some time ago and the verdict was that where its seen on video its the cameras shutter thats causing the effect. Its not possible to scan that way because of the speed of light.

As for the colour effect, I can see it being possible by having a beam animation in which subesquent frames are coloured differently and the frame rate / interval is such as the pattern repeats throught the sequence, each frame appears to chase the other. Would have to test it to know if it works though but I can't see any reason why rescanning fast enough each time with a different beam colour wouldn't give a chase effect.

[instinct]

Anyone have a video of this? Is it like a color scrolling effect?

[White-Light]

Its easy to do left to right. I can think of several ways of achieveing / controlling it.

However, I think its impossible to do front to back because of the speed of light, if you've ever seen it fron to back then I can only imahine its some kind of camera illusion - remember the beams are travelling towards the audience at: 299,792,458 m/s!!!

At a distance of 30m and assuming 3 colours would be chasing at the same time, you'd need to change colour every 10m. That would mean the colour would have to change every 1/29,979,245 th of a second with no down time in between!!! Apart from the fact that it would be impossible to modulate at that speed, even if it were, the light changes would occur faster than the eye could ever register it.

[flecom]

speed of light.

well theres your problem

[Eidetic]

well theres your problem

Not necessarily perhaps. I did a small experiment today that suggests to me it might very well be doable, with the technique pretty much laid out here. It might take me a few days to get to a more controllable test, but I will. There's a brand new (probably first in the US) Japanese RGB laser in my loading dock ready to be unpacked and commissioned.

[White-Light]

The only way I can see it could happen front to back is with persistence where the eye is still seeing whats gone from a fast scan. However, I would have thought the brightness of the next colours beams would have been sufficient to overwhelme the peristence of the previous colours.

Like I said, side to side chasing is no problem, just needs an animated beam, only front to back.

One possible solution for a back to back chase would be to mount a projector at the side of the audience, project a liquid sky and chase it side to side, but obviously from the audiences perspective it would be front to back. If you mounted the projector so far back / used wide angle scanners, so the whole of the audience was under the fan, then it wouldn't be obvious it was a fan apart from the slight slant to the chasing beams. Another way of doing this would be to use many projector mounted side on, each one projecting a narrow beam and have the projectors chase one another, so each projector only projects one colour aat a time.

[instinct]

Wooah.. you mean like my attached image? I'm pretty good at MSPaint. I don't see how you could do it without changing the speed of light (not really that difficult, I have plans ) or by a side projector using a scrim, it would be more like a magic trick/optical illusion, which would be awesome as well.

[allthatwhichis]

Wooah.. you mean like my attached image? I'm pretty good at MSPaint. I don't see how you could do it without changing the speed of light (not really that difficult, I have plans ) or by a side projector using a scrim, it would be more like a magic trick/optical illusion, which would be awesome as well.

I tried for an hour or so last night with Pango's abstract generator and couldn't do it. I think part of the problem is our persistance of vision. I don't think we can "see" that fast.

[Heavyen]

All you need is high lying fog?

[instinct]

I tried for an hour or so last night with Pango's abstract generator and couldn't do it. I think part of the problem is our persistance of vision. I don't think we can "see" that fast.

Exactly. Like when we use a laser, we just see the beam, we don't actually see the beam moving through space, even though it is.