LED Disk Lights

[BobJ]

We want to put up some 2 foot diameter lights that change color (via DMX). But due to the scenery design whatever we come up with must be very shallow. 6" or perhaps a little more. I thought of using a RGB LED wash behind a translucent panel over a circle cut in wood and packing bubbled shower curtain between screen and LED to diffuse the light outward. Or, perhaps there a DMX controlled light ropes we can wind around into a circle. Ideas?

[DrV]

Sounds like a job for LED tape.

[timsabre]

Sounds like a job for LED tape.

 

Agreed, I would make a light box with a translucent panel on the front and white painted interior, then put several runs of LED tape around the perimeter facing inwards. You'll need to experiment with the box depth and position of the tape to get an even light.

 

You can also buy plastic sheet designed for edge-lighting, it has a grid etched into it to pick up the light and you just put the LED tape directly onto the panel edge, it's quite expensive though.

 

[BobJ]

Looking at the LED tape which seems that it will do the job. Big question is can we dim same? I can't find any DMX controlled ones so assume I'll have to hang a dimmer pack nearby and portion power through that. Any one with pratical experience and names of products would be welcome. I'm culling tons of stuff but having problems with the dimming aspect.

[ImagineerTom]

it's not quite that simple - dimming RGB LED tape requires specialist controllers - you can't just plug them in to your existing dimmer.

 

Since you're not in the same country as 99% of this board any recommendations we make about specific kit will be useless. You need to find a local supply of "RGB LED tape" and then ask them to recommend a DMX controller and power supply that will work with their tape. There's not universal standardisation in how LED tape it wired/powered/controlled so in this specific instance you should be looking for someone who can supply all the equipment you need and who will tell you exactly how to connect it all together.

[timsabre]

You run the LED tape using a DMX driver. The DMX driver needs to be powered with a 12V or 24V mains power supply - depending on if you get 12V tape or 24V tape.

 

This ebay link is a typical sort of thing - they all come from China so you should be able to get something very similar in your part of the world

https://www.ebay.co.uk/itm/PX24506-DMX-Decoder-Driver-RGB-Amplifier-Control-Controller-For-LED-Light-12-24V/153055580049

 

[Tomo]

Note that the "ebay specials" like the one timsabre linked to are usually pretty awful, with very uneven dimming curves.

 

Depending on what you're doing, that may not matter.

 

The keyword for the LED tape DMX dimmers is "Constant Voltage". Aside from that, it has to work with the voltage of the tape you get and have sufficient dimming outputs.

 

3, 4 and 8 circuits are common.

[alistermorton]

Indeed. We have a 6 channel eBay jobbie that cost about 15 quid and a 2 channel RC4 wireless dimmer that cost about 12 times as much. It shows. The cheapo is pretty savage and steppy. The RC4 is beatifully smooth.