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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => Lighting Forum => Topic started by: Tim Weaver on November 08, 2018, 09:08:02 AM
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I’ve been meaning to show off this little project for a while. I finally got around to it last night.
How its made:
https://imgur.com/gallery/RtpCaTH
(https://i.imgur.com/pjFloIf.jpg)
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Very cool!
I wonder if there is a way to push the Chauvet Colordash further into the Fresnel so less light is wasted?
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Yeah that is pretty neat. Good job. I love doing things like that.
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Very cool Tim, thanks for sharing! I've been wondering about such a project myself. I much prefer the look of a solid lens over the 4/5/6-in-1 LED grids. Along the lines of what Nathan's thinking, I wonder if there's a way to take this a step further and transplant the guts of the COLORdash into the fresnel itself instead of physically merging the two? Cooling and shock hazards would need to be addressed here, but I'm sure it could be done. One of these days I'll have to take a go at it and see what I come up with. Thanks again!
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Very cool!
I wonder if there is a way to push the Chauvet Colordash further into the Fresnel so less light is wasted?
That was my first thought as well, but the LED only illuminated the center of the fresnel lens and the beam and pattern were poor. I was really hoping to have the LED completely inside the can, but no such luck for me.
For my use, nobody can see the back of the light, and they won't really be moved so the black wrap is fine.
To be fair, none of the light is "wasted". I just had to pull the LED back that far to let the beam fill the fresnel lens from edge to edge. The black wrap is to prevent spill out of the back of the can.
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That was my first thought as well, but the LED only illuminated the center of the fresnel lens and the beam and pattern were poor. I was really hoping to have the LED completely inside the can, but no such luck for me.
Yeah...I can see that happening. I wonder if something like a SlimPar H6 would be a better match for such a project? Maybe there'd be a way to cut off just the back of the fresnel and attach a bracket in such a way a SlimPar could slide in similar to how a gel frame works, but in reverse? I'm not sure if it was here or on Controlbooth, but a while back I saw someone trying to fashion a way to use ETC Source 4 Par lenses in a top hat to give LED Pars a more homogeneous beam. I'm not sure how that ever turned out, but it's definitely something I'd like to pursue further for applications where I don't like the look of the LED grid fixtures. Maybe one of these days!
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Yeah...I can see that happening. I wonder if something like a SlimPar H6 would be a better match for such a project? Maybe there'd be a way to cut off just the back of the fresnel and attach a bracket in such a way a SlimPar could slide in similar to how a gel frame works, but in reverse?
Won't work with the leds so far apart. You need a point source to use a lens.
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Won't work with the leds so far apart. You need a point source to use a lens.
I'm not following. As example, the ETC Source Four LEDs use a grid of emitters of various colors yet still produces a homogeneous beam out the end and can use gobos, irises, etc without issue. While that's beyond the scope of a fresnel, I would think that this would still be effective to some extent - especially if the end goal is to essentially use the fresnel as fancy diffusion. It'd sure be interesting to play with!
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My guess is you get a better result with the lens removed. But it would be fun to try. ;)
Why has nobody made it if it was that easy?
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Why has nobody made it if it was that easy?
There are a handful of full-color LED fresnels on the market such as the Chauvet Ovation F-55FC and F-915FC. Altman also has their Spectra Par, and all of these examples use an emitter grid and not a single-source COB LED. The catch is though, as you elude to, it's neither cheap nor easy to get this right and make a coherent, even field of light that behaves as a homogeneous source.
Why we don't see SlimPars shoved into fresnel bodies is probably because it wouldn't be very practical or useful in terms of what a fresnel is actually supposed to be and the purpose it's supposed to serve. I don't disagree either that the end product would probably be more useful without the lens, or if anything just drop some diffusion or light shaping filter to give the homogeneous look...but then again that also defeats the purpose of transplanting the Par into the Fresnel in the first place!
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I've been looking for pictures of the inside of the above mentioned grid based fresnels, but sadly couldn't find any. But from the three mentioned only the f915-fc uses a real fresnel lens. The other two only make it really hard to look through the glas. ;)
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FWIW, I gutted an 8" fresnel and dropped a 1/4 watt par fixture into it. While it does "work" there is a multicolored "litebrite" look to the fresnel lens. It doesn't look nearly as good.
I was hoping to use the 8"ers around the stage on floor stands to enhance the look.
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I've been looking for pictures of the inside of the above mentioned grid based fresnels, but sadly couldn't find any.
Here's the emitter PCB from the 915:
https://www.chauvetparts.com/product.htm?pid=267437&cat=20787
If you've never seen the insides of an ETC Source Four LED there's a How It's Made episode (https://www.youtube.com/watch?v=aOBqb817gJE) that gives away a few secrets too. To argue against myself, yes, it's definitely more compact than the front face of a 6-in-1 SlimPar Pro, but I still think with a bit of fidgeting it'd be viable to some degree, for the purpose only of creating a fixture with a single lens that mimics the "old school" look of stage lights. That's why I mention the Spectra Par - that's essentially what they're doing, optics aside.
FWIW, I gutted an 8" fresnel and dropped a 1/4 watt par fixture into it. While it does "work" there is a multicolored "litebrite" look to the fresnel lens. It doesn't look nearly as good.
That's interesting. I wonder if a sheet of diffusion upstream of the lens would help to mask that?