Making a star cloth

[mac.calder]

I need to make a large star cloth, and want it to be a fairly detailed one, with lots of twinkling etc with varying depths and intensities. There is another factor just as important - cost.

 

What I am thinking will take up about 6 channels on my dimmer, which I can probably live with, but I want suggestions for improvements.

 

My first idea:

 

I can cheaply get boxes of 100 fairylights, so I was thinking, just use electrical tape to black out the odd light, then attatch to some scrim or something like that, in a fairly random order, and use say two strings per channel starting at different positions(It is a fairly large area that needs to be covered), then plug each one into a dimmer and program a chase with quite a few slow fades between say 35% and 80% intensity. The depth of the lights (as they always end up turning arround and facing odd directions) should give an idea of depth.

 

The main problem is that would have (using 6 channels) six regions always changing at the same time.

 

So I went back to the drawing board, and thought- what if I connected multiple bulbs together from different channels using almost random alocation (and have the odd one alone), then I would get larger ones, small ones, and it would effectively increase the number of groups I have, although I would need about twice the number of lights.

 

They are two methods I thought of, then I thought about using LED's - but they are too expensive, and designing a multi channel 'twinkling' circuit more trouble than it's worth.

 

The place I am building this for does not want to hire one ("I can think of a million and one uses we will have for one if we have our own") and will not pay the $$$ for a proper one that 'twinkles', and one that is basically a set of fairylights poked through holes in fabric are "Too artificial", so I am stuck with building something.

 

The dimmers are fine (apparently) with inductive loads.

 

And before replying with the fact that fairy lights exist that have chase/blink circuits and the like within them, they are usually fairly in your face (on/off), and often remain 'on' for a minute before starting their blinking and cost twice the price of the cheap ones.

 

Oh and if anyone has any idea about what sort of 'lights per m^2' I should use, I would be most greatful.

[paulears]

A couple of things come to mind -

Fairy lights are not that reliable, you'll start to lose them and then others die, just like Christmas tree lights. The other thing is that they're quite heavy and fixing the things is VERY time consuming. The cable weighs quite a bit.

 

You can get cheap fibre optic ones (I think CPC again) that have proper through cloth fixings.

 

As for layout, depends on what you want to achive. If you have multiple dimmers then there are plenty of options in terms of chases etc, but for them to look good, you need to make sure each lightsources tail ends are not just in one area. If they all overlap then lovely warpy effects happen as colours change at different times - any form of regular placement looks obvious, as does over saturation of tail ends in certain areas.

 

I have to say that the overall success is more linked to your artistic ability, than your technical one. You have to visualise the effect you want to get, then plan it - then make it happen.

 

If I was to be very honest, my attempts (3 so far) have actually been a little iffy - well, actually one was dire!

 

Replacing the colour wheel with a modified gobo with spoke pattern worked very well (I thought) - great random white twinkles. Colour changes get boring very quickly.

 

Maybe, if the cloth isn't too big, a colour and white version?

[3guk]

http://www.dj-community.co.uk/lore/article.php?id=020

 

I know its for djs but it might help you. You could do a similar thing ;)

[mac.calder]

As far as dodgeyness of fairy lights, I know that one only too well. The fixtures I can get for very little money are actually 10 strings in paralell, so troubleshooting blown globes is relatively easy, and they are 12V - which typically are not overly heavy wires when you take out the weight of the transformer.

 

I realise that how it looks is dependant on artistic ability, I was thinking about downloading some star charts and using them - that way those astrologically minded people who watch which ever lame show this company puts on can play "Spot the constelation".

 

As for plug ends, that is no problem, as it will be stretched across a frame, allowing me to gaff extension leads to wherever they may be required.

[Grahame]

The whole secret with fairy light starcloths is to hang a black gauze downstage of them. That way the small movements of the gauze will make the lights appear to twinkle. If you lightly spray down some of the lights with black spray paint it will make them appear of varying brightnesses. The gauze also masks the ugliness of the dangling bits of wire!

 

I'm touring such a set-up at the moment. The starcloth is made from one of those sets of a hundred low-voltage lights. The strings have been cut up and bodged together in different lengths and spacings so that no regular patterns of lamps are visible, and they're suspended from a "bus" length of wire that is attached to a long length of black sash for hanging. The whole thing runs off a very small 12V tranny and works a treat.

[andy_s]

I got some fairy lights from Stage Electrics - made by a company in Taunton, which had nice connectors at each end of the string, so you could link I think up to 3 strings together from one plugtop - this doesn't help your twinkling, but might be a useful thing in terms of no grelcos or choc-block....

 

incidently - one job I had as showcrew was to lean (carefully) over the fly rail and "manually stimulate" the end of the bar that the starcloth was flown on, to achieve the effect described in the above post.....

[jfitzpat]

FWIW, I've had pretty good luck with plastic fiber optic cable. Stick strands of the fiber optic cable through the material from the rear, and secure with blobs of silicon. Route the fibers to a bundle, which you glue with clear epoxy. When the epoxy is hard, cut the bundle to a flat edge and polish it with very light grit sandpaper.

 

Nip down the protruding ends with a hot wire or soldering iron. Don't use electrical cutters, they crush the fiber and cut down the light that comes out. You can then illuminate the bundle with an incandescent lamp, like a projector bulb, and get sparkle and/or color with a little color wheel on a DC motor. If you want patterns, instead of random, make the bundle and color/pattern wheel first, then route the fiber to the material.

 

As Grahame mentioned, gauze or scrim helps the effect a lot.

 

-jjf

[bruce]

Grahame,

 

Sounds interesting. Any photos?

 

Bruce.

[Grahame]

Here's one from an earlier show...

http://img278.echo.cx/img278/5999/bcsetsmall4ck.jpg

 

This from 'The Bright-Eyed Mariner' by Tabula Rasa Dance Company. This had a painted blue gauze instead of a black one (you can actually see the marks of the paint frame in the photo, but it wasn't that obvious in real life!), but the twinkle effect is the same. The moonbox was also home-made, and could display either full or crescent moon thanks to a swivel-mounted cut-out cover and an amazing lash up of string and pulleys!! ;)

I had everything up at full for the purposes of this picture - at a lower level the stars look a lot better than they appear in the photo.

 

Thanks to ImageShack for Free Image Hosting

[stevep]

further on what "jfitzpat" said about using fibre optics - Ive been using a fibre optic one up here for a 16ft drop / 30ft width - the light source is an optikinetics solar 250 with a stanadrd colour wheel in it - the 250w source is certainly bright enough to do the job

[dbuckley]

(first post)

 

About 15 years ago we built a "star wall", which was like a star cloth, but made of four panels of solid material, each 8x4 feet, so 32 feet wide, 8 high. Low cost was an important consideration!

 

We rewired several sets of christmas lights into 36 strings of (from memory) 5 lamps each, for a total of 180 randomly placed lamps, These were then connected into a 6x6 matrix, driven from a controller I built. The controller used two eproms with patterns for X and Y directions (patterns generated using a quickbasic program), and darlingtons and power transistors. Power supply was a 24V 1000W transformer. Strings were either normal, bright or dim. The matrix was scanned at just over 20KHz, to keep switching noise out of the sound system. All analogue, with +10V control. These days you could use a PIC... The matrix didnt have steering diodes, so the strings all interreacted with each other...

 

To be honest, it probably wasnt a very good simulation of stars, but it looked great, we were very happy, and used it on several subsequent shows.

 

So yes, it can be done.

[Grahame]

Right, I have just struggled through a show using a 4-channel white LED starcloth belonging to the venue, instead of my touring fairy light/black gauze combo shown above, and I can't say I was impressed. For one, it chewed up channels on the desk. Second, I had to plot a chase to get them to twinkle, and it had to be a pretty complex chase to look convincing. Third, if the levels were anything over 12% the stars looked like supernovas! Fourth, I had to manually implement the chase in every cue I needed the stars in; this inevitably led to them being plotted in to some states, resulting in a non-twinkling starcloth! I probably could have done this better if I was more familiar with an Avo Diamond 4 and had time to play with it, but on a one-night gig I didn't have that luxury. And finally, I really wasn't impressed with the LED distribution; they just weren't random enough and the overall effect was pretty poor I thought.

Sometimes too much technology just gets in the way - I should have hung the gauze and fairy lights. But at least I now KNOW that they look better than an expensive LED cloth! K.I.S.S...! :(

[peter]

...it chewed up channels on the desk. ....an Avo Diamond 4

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Eh? You're not suggesting that you couldn't find 4 spare channels out of 4096?

[gareth]

I beg to differ re. LED starcloths - I think they look the mutt's nuts. A lighting rental company a few miles away from me rents out part of the upper level of their warehouse to a company who manufacture LED starcloths. I've seen some of the cloths they make, and they look fantastic. It's only partly to do with the actual technology - part of it is what you do with it. A badly-made LED starcloth is going to look bad, of course - but then, a home-made starcloth using 'traditional' pea lamps or grain-of-wheat lamps is going to look pants if it's put together by someone who doesn't have a clue.

 

Edit : oh, one more thing - I'd also be interested to know the answer to the question that Peter asked - what did you have hanging on the end of the other 4000-odd channels on the console that made it so bad to have to allocate 4 to the starcloth?! :(

[JimWebber]

...it chewed up channels on the desk. ....an Avo Diamond 4

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Eh? You're not suggesting that you couldn't find 4 spare channels out of 4096?

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Yes, but were there 4096 dimmers?