From The Horse's Mouth

LED technology is changing almost weekly. As you look through the trade magazines, you will notice that there are many LED PARs out there. They all look the same but the features are very different. Some use 3 watt LEDs some use 1 watt LEDs. Some have an amber channel along with the RGB channels, some are only RGB. Some use separately mounted red, blue, and green single LEDs and some have RGB LED chipsets. So what is the difference?

1 watt versus 3 or more watts LED
If you are hoping to match the lumen output of a 1,000 watt PAR with an LED, you have some waiting to do. You will not find anything in the price range of an incandescent PAR can to match with LED fixtures. The 3 watt LED fixture is certainly brighter than the 1 watt fixture but will need bigger fans and in some cases will shorten the life of the LEDs by overdriving them. Remember when buying most LED fixtures, the entire fixture is thrown out at the end of its life cycle not just the lamp. Higher LED output does come with louder fans and releases more heat,  but in some larger facilities, club and rock venues, noise and heat is not an issue. As you look at higher wattage LED fixtures, the price goes up as would be expected. Some LED PAR fixtures are weighing in at $2,200 each. In my days in the biz, a PAR can was something that when it fell off the truck, you just threw it away because they only cost $60. They were really only metal road cases for the expensive PAR lamp.

Light distribution
When you place regular diffusion on an LED fixture, odd things happen. The fixture usually uses multiple light sources so you will not get the even light distribution that you would get with a single source incandescent lamp. Some manufacturers offer a holographic etched lens that looks like diffusion but is far different optically. Edge blending can also be an issue. Multiple lower wattage units as opposed to less brighter LED units might be a good way to provide an even wash on the stage or wall.

Red, Green, Blue or RGB plus Amber or White
Using primaries, you should be able to mix most any color that you would need. Having that amber channel is nice to warm up a color but is not necessary as anyone who has used RGB and RGBA cyc lights will attest to. Some manufacturers are adding a white channel which will help “pale” a color mix and add lumens to the stage but is akin to having a white circuit on your cyc wash. In the old days, a clear or no color circuit on overhead strip lights, on a stage, were handy to use as work lights and were brighter because of the lack of roundels. However, with LEDs, mixing colors to get white works just as well.

White LED fixtures
These fixtures have more lumen output than the RGB fixtures but will still require color filters to create colored light. The fixtures will have a much lower wattage consumption than their incandescent counterparts but will not give you the immediate color changing capabilities as the RGB fixtures. White LEDs  are a good way to have the brightness that is necessary until RGB LED fixtures catch up to the theatre world’s need for more output.

Finally, many manufacturers state what the fixture’s LPW is in the specs. This stands for Lumens Per Watt and indicates the efficiency of the light source that is being used. We already know that the LPW for LED fixtures are much higher than incandescent sources but what the customer should calculate is the DPW (Dollars Per Lumen) of an LED fixture. In some cases a brighter, punchier AND pricier LED fixture is needed and in other cases a lower wattage but much less expensive LED fixture will do the job just fine. Before buying, do a shootout with several LED fixtures to check the fan noise, color temperature of the LEDs (they vary from brand to brand), and light distribution. Also, don’t forget to run the fixtures up and down with a DMX board to see if the fades are “steppy” or abrupt at the end. Take into consideration the useable life of the LEDs, they range from 100,000 hours to 50,000 hours and recently I have been seeing 25,000 hour estimated life on the LEDs. In some cases, as the LEDs are overdriven for brighter output, the manufacturer drops the lifespan of the light source or in other cases the entire fixture as the LEDs are not user replaceable. Set the LED fixtures next to an incandescent source with a color filter and see how difficult or easy it will be to color match the two (believe it or not, there is a big difference in color matching).

Don’t forget to include in your shootout , Apollo’s Multiform LED 1009 & 1018.  Contact an Apollo sales rep or dealer to put a demo to the test!