LED Fixtures for downlight - how they worked out in my Theatre

Discussion in 'Collaborative Articles' started by JChenault, Jan 2, 2011.

  1. JChenault

    JChenault Well-Known Member

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    Recently we made the move to LEDPar cans’ in our theatre. Since this is a topic that many on the board will face, I thought it might be useful to share my experiences.

    Our venue is a 380 seat converted movie theatre that does only Musicals. We have 60 dimmers for a stage that is 34 feet wide at the apron, with a 24 foot wide proscenium. Pipes are low and throws are short – over the stage the pipes are dead hung at 16-6 above the stage floor. We currently have two moving lights, and 12 Morpheus color scrollers that we devote to our side lights.

    Our plan was to purchase some LED PAR units for downlight over the stage. The idea was that we could free up a number of dimmers and fixtures that we currently use for downlight.

    We ultimately decided ( in large part due to cost) to buy a Chinese unit made by Longman. (Cost was about $350 a unit). This was a RGBAW unit with 36 3Watt LED’s. We got a 40 degree demo unit an compared it to some Elation products and were favorably impressed. At the price point it looked like a great deal.

    When the units arrived, we discovered on installation that we had 19 degree units, not 40 degree units. The manufacturer had supplied (To the distributor ) the narrower units without notifying him. Additionally the fan in the units seemed quite a bit noisier than in the demo unit. Instead of sending them back, we disconnected the fan and put a frost in front of the unit to give us enough beam spread. We also had an issue with the size of the hole in the yoke. It was too small for a C clamp so we had to drill them out just a bit.

    Installing the fixtures was actually more difficult that I had expected. I chose to make my own DMX cables in order to save some money, and it made me appreciate just how much time building cables takes. We had to run new power cables ( Got an extension cable with outlets space along it ) to the fixtures. We had to re-route our DMX cables to get to the lights. The installation of the 11 fixtures took the better part of a day and a half after the cables were made up.

    Our first show using the units was White Christmas, and they worked very well. It was very nice to be able to change colors quickly and relatively easily. It added a lot of flexibility to the rig. Even better, it freed up fixtures and dimmers that I could use for other purposed. In general I was pretty happy.

    Lessons learned.
    • Don’t order based on a sample if you are not sure of your manufacturer. You may not get what you saw.
    • Give yourself plenty of time to get them up. Running a lot of new power cable and DMX cable is not hard, but you want to be very clean to get the DMX and power ( which we expect not to move too often) out of the way of the other cables which we move around for every show.
    • The intensity of the fixtures for intense colors is very nice. I can make a red or blue wash that is as bright or brighter than an equivalent 750 watt 6 inch Fresnel.
    • Amber is a bit dim. I had colors making good warms. Some of this is due to the white LED which, in these units, is quite blue and makes things a bit harsh. Next time I will look for a warmer feel in the white light.
    • The Amber and White do extend your range and intensity over just using Red / Green. I would not consider an RBG unit for this kind of application.
    • When evaluating the units, they were a bit steppy. ( IE a slow fade was jerky when dim). This turned out not to be a problem in production. There was always enough other light on stage that the stepiness got washed out. ( We also used the units to provide shift lights so the blues never went completely out).
    • When I have seen LED units, there has always been the issue of color fringing. I could not see any fringing in our application. I think this was because we typically had some incandescent on as well as the LED units, and that the LEDs were only used for down light.
    • There were some issues with the speed and dimmer curve of the units vs the curve of our incandescent. I spent some time in blackouts putting a delay in the LED units so they would more closely match the tungsten.
    • Take some time at the beginning to build up the color palettes ( or to define the colors) you plan to use in the show. Using a Chinese unit means existing palettes will be unlikely to work.
    • If you can, get a unit that has a color frame. We had to tape our frost gel and black wrap to the unit instead of being

    Now would I rather have gotten some Seladors – sure but they were way beyond my budget. I’m convinced that, for certain applications like down light, LED’s are a good solution right now.
     
  2. Les

    Les Well-Known Member

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    Thanks for this article. It is certainly helpful. One thing I am concerned about, however, is the longevity of the fixtures since you disconnected the fans. Might I suggest purchasing new, high quality fans as a fix? I'm sure the fans in your units were of the lowest quality possible. It shouldn't be too difficult to find better fans.
     
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