Diffusion for LEDs

[numberwrong]

I'm sure that this has been covered on blueroom before but I cant find anything relevant in the search...

 

Is it posable to smooth out the actual light source of an LED PAR so you can't as easily see the individual hot spots of each LED. I'm thinking in a situation when the fixture is used as back light, say for a band facing the audience or as a blinder.

 

I understand you're going to lose a lot of output. Think of it as more an effect as oppose to actually lighting an object/person.

 

I've been told LEE 228 - Brushed silk, used one way then the other works.

 

http://www.leefilters.com/lighting/diffusion-list.html

 

I'm not thinking of an actual situation or particular LED product here. Just would like to know what BR thinks before I buy a load of frost and diffusion to play around with!

[Ynot]

Getting 'rid' of the individual RGB points of light from an LED can is going to be nigh on impossible because whilst a frost may well diffuse the beam a little better (and yes, at the cost of light output of course), giving a more mixed colour effect there, it won't do anything close to the point sources. If you could mount the frost/diff a fair way from the cans, then yes that would have the desired effect, but we're talking at LEAST several inches from the can, and that just isn't practical.

[timsabre]

You can do it, but you need quite a lot of separation between the LEDs and the diffusion, the spottier the LEDs the more distance you need if you want a properly mixed output. Just putting diffusion in the gel frame may not get the effect you desire.

[mark_s]

I had good success using a Source 4 PAR colour extender (in an LED PAR with the same accessory size as a Source 4 PAR) and a cut of Leelux when I needed to do that some time ago. The colour extender gets the diffusion far enough away from the LEDs that you see one solid colour on the diffusion rather than a lot of red/green/blue spots. The Leelux was mainly because I wanted a very diffuse source - something lighter may work just as well.

[mac500]

A bit of rosco 119 frost or 132 works perfectly well and doesn't extend the beam like the brushed silk would

[gyro_gearloose]

Just a thought, but what about using some diffuser panel from a florescent light? I'm not talking about the diffusers from single or twin tube fittings, but rather the sheets used in office lighting. Its the stuff at the bottom of this page. A bit of this with some mild diffusion material might get you the effect you're after.

[MarfaLights]

Does anybody know what ETC uses on the Desire line of LED units? I think the standard configuration is 25 degrees but a secondary lens, which looks like frost but is not, covers the face to give you other field angles. I had these fixtures demo'd at our venue and was certainly impressed.

[Ynot]

Does anybody know what ETC uses on the Desire line of LED units?

If it's a similar idea to the Paletta range, then they use ridged lenses with a variety of field angles. But even those won't hide the fact that there are multiple point sources in the fixture.

[Tomo]

The Desire range use holographic lenses to produce a well-merged beam that has no coloured shadows.

 

However, you will still see the dots of colour on the face of the lens if you look directly at it - this can only be avoided by frost at a distance from the fixture, as timsabre said.

[lite_lad]

There was a topic a while ago and one of the suggestions was the paper that comes with sheet of gel, I was pretty sceptical but thought it may be worth a shot out of curiosity and its not half bad! especially as its free! and im sure some experimentation with different kinds and thicknesses of paper may achieve some good results!