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LED Fixture beamwidth


randallr

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About the diffusers, for about $6 a sheet, Rosco produces a "Light tough silk" It has lindentations running the length of the sheet, It's used on Cyc lights which are taller then they are wide, and by putting the lines a diffrent direction it will widen the beam.

If you put it over your Lights, it will widen them alot. even tested with a flash light normal beam is 1" with this it gets to be a little more then 3".

Its R160 in the roscolux line of Gel.

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Randall I noticed you said you had a 1700 watt fogger. It wouldn't happen to be a Martin Pro Magnum would it? That is what I have and it is 1700 watts. I need to get it fixed because the heating element is going out. I have about 6 700 watt foggers and 4 400 watt fogggers also but they are not DMX so they do me no good except for different elements in my Halloween display. I normally use my 1700 watt for my fog chiller to get yard coverage and I was going to use it in this years display since it is the only DMX fogger I have.

Have you guys tried to shoot your fog through a fog chiller? Their are several DIY videos and web sites out there you can make one cheap out of a cooler. It will allow your fog to hug the ground and last longer even with a steady breeze. I do this for Halloween and it works great. Of course for Halloween is only one night a year so you only have to keep up with the ice for one night. I would highly advise agaisnt those ground laying foggers you see at Wal-Mart, Spirit, Party City etc. They are horrible, I got one to try and took it back and just made more fog chillers.

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This is Lee Filters site for diffusion gel. This is really the way to go rather than using a hard plastic sheet. A "sheet" of gel at about $6.00 is 20"x24" and will last forever on any fixture in which heat dissipation isn't a problem. LED fixtures don't get hot enough to even come close to distorting this gel.

http://www.leefilters.com/lighting/products/range/ref:I46C9C14F8BA5B/

Charles

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The basic rule of photometrics is this:

Double the distance and the light...

1) Has twice the field diameter and
2) Has 1/4 the illumination (in footcandles)

OR

Half the distance and the light...

1) Has 1/2 the field diameter and
2) 4 times the illumination (in footcandles)
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Here is a nice little chart

http://www.etcconnect.com/minisite/sourcefour/metrics.html
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Beam angle is the point where the light emmitted by an instrument is diminished by 50% when compared with the output at the center of the beam

Field angle is that point at which the light output diminishes to 10% of the output at the center of the beam
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Illuminance is a measure of the amount of light falling on a surface.
One footcandle is the illuminance at a point on a surface which is one foot from, and perpendicular to, a uniform point source of one candle.
One lux is the illuminance at the same point at a distance of 1 meter from the source.
One lumen uniformly distributed over one square foot of surface provides an illumination of 1 footcandle.
____________________________________


I will stop for now.



Charles

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I've got a 1700 Watt and 2- 1250 Watt Chauvet's with the DMX interface ($25) which takes place of the wired remote. Only bad thing is that's going to really shoot up my electric bill, keeping them warm all night for a few short scenes...

My porch is about 30' wide and 6' deep. I'm planning on having the 1700watt in the middle shooting against door, and the two 1250's on each side pointing inward. I may put a couple of 700 watt units in some type of enclosure a little ways out also.

I'm only going to use the effect a couple of times for a short period. The Intimidator moving yokes are going to be mounted between the top of the columns on the porch.

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michael.farney wrote:

How were you planning on keeping the foggers warm so the fluid doesn't freeze?

The fog machines keep themselves warm, and you control the fog output, just like if you kept it plugged in and hit the button..only with LOR.
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michael.farney wrote:

How were you planning on keeping the foggers warm so the fluid doesn't freeze?


The foggers power supply won't be connected to a LOR power supply. Since it is 1700 watts which is about 15 amps it will most likely have it's own dedicated circuit. So it will be on constantantly staying warm which is safe nothing wrong with them being on. Then LOR through the DMX would control when the fog blasts will occur. Also fog fluid doesn't freeze. Atleast not at temps that any one would see around here.
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michael.farney wrote:

Texan78 wrote:
Also fog fluid doesn't freeze.

What about sub zero temps you see in Illinois?


Since fog fluid is glycol-based or glycerine-based it would take about 40-50 below 0 to even get it to crystallize. You should be fine in Illinois, it takes a lot to freeze it if even then.

The only problem you might have which I wouldn't see it as a problem. If you have freezing or below freezing temps you might have a hard time having getting the fog to rise and disperse. The hot fog coming out will hit that cold freezing air and it will cause it to linger and fall to the ground. It won't be a instant thing but onces the fogs cools off it will fall to the ground instead of floating up. That might or might not be a good thing for you. As far as the juice freezing it wouldn't be a problem.
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Texan78 wrote:

michael.farney wrote:
Texan78 wrote:
Also fog fluid doesn't freeze.

What about sub zero temps you see in Illinois?


Since fog fluid is glycol-based or glycerine-based it would take about 40-50 below 0 to even get it to crystallize. You should be fine in Illinois, it takes a lot to freeze it if even then.

The only problem you might have which I wouldn't see it as a problem. If you have freezing or below freezing temps you might have a hard time having getting the fog to rise and disperse. The hot fog coming out will hit that cold freezing air and it will cause it to linger and fall to the ground. It won't be a instant thing but onces the fogs cools off it will fall to the ground instead of floating up. That might or might not be a good thing for you. As far as the juice freezing it wouldn't be a problem.


This is my last comment on this because I don't want to hijack the thread further. I tried it out today at 26 degrees. The fog definitely cooled. A small amount hugged the ground, but the rest stayed anywhere from 0-25 feet. It was perfect for keeping fog in the yard longer.

Let's start a new topic if we want to discuss foggers further.
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