Theatre project needs super bright source, hard shadow.

Hi all,

This is for a theatre project I am developing as a designer, can anyone help me?

I want a superbright, (cool, so LED is perfect) single point source (for hard shadow) light source. Doesn't have to be battery operated, but should be equal in lumens to a 100 watt bulb or better.

Anything? I have heard that the SSC P7 Bin C 900 Lumen LED is pretty amazing. But is it possible to get any brighter?

The Shadow Man

Not sure if you're going to be able to do this with a LED. How far away is the light source going to be from where it is projecting?

I know I have seen incan based setups that use a lens to focus the light for this type of job, and you can insert cut outs into it to project a perfect shadow of whatever shape you insert.

if its what i am thinking, you need a proper spotlight thats used for stages.

Crenshaw

faulknerfilm said:

Doesn't have to be battery operated, but should be equal in lumens to a 100 watt bulb or better.

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A 100W bulb incandescent puts out between 1500 and 1700lm. There's no point source LED on the market that can match this. The best that can be done with an LED would be an array of two P7s behind optics, but this would give you a double-edged shadow unless the light source is well away from whatever is casting the shadow. LEDs aren't going to work if you're looking at casting shadows through a gobo mask.

Your best options are probably to use an incandescent and put up with the low color temperature or go HID and put up with the high cost.

I think that when you are looking at a single point light source, the 100 watt incan VS P7 becomes an interesting comparison.

The 100 watt bulb may emit over 1,000 lumens but it does so in a spherical pattern. The P7 may put out 1/2 the light, but it all goes forward.

My 3 watt 150 lumen LED pocket light overpowers the light from the 150 watt, 1,000 lumen floor lamp next to me. An easy way to see the effect is to find something where the floorlamp is casting a shadow, and shine your 150 lumen on the shadow. In my case the shadow disappears.

Of course, you can also just use a light meter, but shining your light on things is more fun.

With small lights like the Fenix P2D available for under $75, it's easy to build a test bed to see if a humble Rebel 100 or Cree Q5 will do what you want with only 150 lumens or so.

You do have some small, bright lights, Right?


Daniel

Is there a reason you can't use Source-Fours?

This has probably already been said, but 100W halogen=1500 lumens. No chance with current emitters- you're better off staying with incans for this project due to heatsinking problems, driver problems, optic problems, etc.

Jarl said:

This has probably already been said, but 100W halogen=1500 lumens. No chance with current emitters- you're better off staying with incans for this project due to heatsinking problems, driver problems, optic problems, etc.

Click to expand...

Did you read above? A P7/MC-E emits light in a pattern such that it can equal the output of a 100W incandescent in one direction (i.e. no reflector for the incn bulb.), depending on the application.

I think this is what you want
http://www.americandj.com/ProductsList.aspx?MainId=0&Category=L.E.D.

gadget_lover said:

The 100 watt bulb may emit over 1,000 lumens but it does so in a spherical pattern.

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That really depends on what kind of 100W incandescent bulb you're dealing with.

Incandescents for theater use tend to be directional PAR lights. A 100W GE PAR38 with a ten degree beam pattern puts out 1470 lumens and is specified to produce 30,000 candela at the center of the beam.

1 candela = 1 lux @ 1m.

Perhaps something like this with an aspheric lens....

http://www.dealextreme.com/details.dx/sku.5848
- Input voltage: 18V~20V
- Total power consumption: 20W
- Output: 800 Lumens Total (manufacturer rated)

What size and how far away?

A(or a few) current gen LEDs coupled with a custom or pre-made elliptical reflector might work. I don't know where the lens should be(at the other focal point?) but that should collect most of the light and produce a well throwing beam.

:welcome:

Gunner12 said:

What size and how far away?

A(or a few) current gen LEDs coupled with a custom or pre-made elliptical reflector might work. I don't know where the lens should be(at the other focal point?) but that should collect most of the light and produce a well throwing beam.

:welcome:

Click to expand...

The FP of the lens should be the second FP of the reflector. There should also be some sort fo shielding to keep spill light from hitting the lens.

I don't know of any preexisting solutions for this though.

Thanks Luke A, I've been wondering that since I realized that elliptical reflectors can be used well with a lens.

A custom reflector might be needed.

If this is the kind of effect your are looking for, i dont think LEDS can help you much yet.



better off looking for a true spotlight.



Crenshaw

Here is a pro lighting supplier of LED fixtures
http://www.elationlighting.com/category.asp?category=LED Lighting

Sable said:

Is there a reason you can't use Source-Fours?

Click to expand...

Yea, you're better off going straight for the best if you can. Color temperature can be corrected with filters.

@faulknerfilm:

You might want to try asking here

http://www.controlbooth.com/forums/lighting/

for some advice on how to get the effect you want.

I think I see what you're looking for. I guess you can't use a reflector or optic since this will diffuse the shadow.

The osram ostar is probably the best LED for the job. If you can find a good bin that is otherwise you're better off with the SSC P7. There are brighter LEDs but they use large arrays of dice and won't give you the point source you are after.

You may be able to get the P7 near to the brightness you require by overdriving. Mount it to a HUGE heatsink and you should be able to drive it up to 4A. You could even try a CPU heatsink and fan. It won't last too long though. Some of the modders here have driven the P7 to 6A for a few seconds.

A better option would be to build something out of an automotive hid ballast and bulb. This would be much brighter but be careful, there are dangerous voltages involved.


BTW: this would be better in the "fixed lighting" forum.

I don't know where to buy them, but Edison Opto makes 50W 3200 lumen LED http://www.edison-opto.com.tw/products_detail.asp?category=1&cno=111
And there are already some chinese manufacturers that make up to 500W LEDs with 20000 lumens.