Does anyone know if there is any type of lights that emit true black light - not purple. I am thinking of a light source that looks like a shadow, as in making an object appear to have a shadow when it really doesn't.

Any help appreciated,
JoeJoe

Hi, JoeJoe!
Maybe I'm misunderstanding your question, but I don't think there is any such thing as actual "black light". Black is the ABSENCE of light. A shadow is a dark shape, e.g. on the ground or a wall, caused by an object (or person, etc.) blocking a portion of light. In other words, a shadow is only possible through the process of BLOCKING a light.
Cheers!

Ummm ... yea, but like umm ... arn't we magicians? Can't we do things that are not possible? That was my thinking anyway. Certainly there must be a way to produce a shadow in a place that there is not sopposed to be a shadow?

Look at Tellers beautiful rose illusion that casts an apparent shadow.

An alternative that comes to mind is a LCD projector used as a spotlight on the prop with the exception of a shadow "image" craftfully positioned.

Actually, the effect you're looking for is quite similar to "Anderson's Ghost," a Camelot Labs effect, with one major difference:

Use the LCD projector, or an ordinary slide projector, to project a black rose silhouette behind the rose on a light backdrop. Now, to really have some fun, use an LCD projector connected to a computer (laptop will be fine) to project an animated GIF of a rose silhouette rising. At the appropriate moment, pick up the rose and trigger the GIF. You can have a lot of fun with this: the rose in your hand goes one direction but the shadow goes another, or the rose in your hand comes out of the vase but the shadow stays put, or you pick up the shadow and the rose stays put, or, or, or!

By the way, I just used a rose in a vase as an example. You can use a Humvee if you want; it doesn't matter. I do it with an actual human who manipulates the objects behind her while her back is turned to the audience but they see them move "through" her because she's transparent. When she turns and slowly becomes opaque, the things the audience saw change (straightened pictures on a wall, rose from a vase, etc.) actually have changed.

The "shadow that isn't a shadow" is just the flip side of this illusion.

Yes, this is done all the time in theatrical lighting, perhaps more than you realize. But it's not a "black" light, since shadow is, as pointed out above, the absence of light, and light suckers don't exist (contrary to odd physics theories you may read online ;o)

It's done by putting a pattern (often called a template or a gobo) in the template slot of an ellipsoidal reflector spotlight (or ERS, sometimes called a Leko after the first such model). The pattern is a metal cutout (although some newer ERS units are cool enough that you can use a pattern printed on an overhead transparency) and, by putting it inside the light at the right point, it will be crisply focused (or not, as the designer prefers) and projected in the beam of light as a shadow. This is how lighting designers in shows and concerts get all those cool looking patterns of light and shadow on the stage floor and sets.

--Andy, currently in Omaha, NE mixing Sesame Street Live

AHHHHHHHH!

I saw an amazing demo of High End Systems DL1 in Austin, TX about a year ago. Imagine a video projector on a moving Yoke. Now imagine you have a computer that can create, edit, adjust, and keysone objects. Well you don't have to imagine this is the next generation of lighting boys. This meens you could creat a silouette on a screen and make it walk around and vanish or do other things like morph. You could also move the screen and use the same unit. You could move the screen while projecting... There are so many things this will soon allow us to do.

Oh and gobos will no longer be needed. You can create any image and project it. This creates some of the most intense beam effects I have ever seen.

Check it out at http://www.highend.com/products/digital_lighting/

Now imagine you have $32,000 to buy one...

Fitz

It occurs to me that you could use the fake shadow brilliantly in a sucker effect.

The vanish happens and the person is thought to be hidding behind something (reasonably obvious) projecting their shadow. So while the audeince can't see the vanished person they "know" he's behind that pillar because they can see his shadow and the pillar's shadow on the backdrop.

I suppose it can't be a new idea. Copperfield used shadows a lot in his past shows.

S

American DJ also sells a lot of lighting as well as projectors for any logo on a transparency sheet to be shown on the wall or anything.

http://www.americandj.com is their site. Also Rosco is the manufacturer for gobos, their site is http://www.rosco.com

High End fixtures are great just way out of my budget for now!

Just some ideas,

Andrew

Love the use fake shadows in illusions. I once built an illusion in which a motorcyle and rider turned into a car with magician inside it for a TV special . It used a combination of various lighting tricks and shadow manipulation.
If any one cares to hear more PM and be glad to share the method with you.

Scott

Special thanks to Ron Jaxon for posting this on his Facebook which clearly answers my question and includes an awesome demonstration on how to turn white light into black light! I always knew it was possible.

https://www.youtube.com/watch?v=p-OCfiglZRQ

-JoeJoe

To be fair, he's simply using some linguistic gymnastics to talk not about creating a true "Black Light" as you're describing but instead a contrast shift. In the presence of a strong enough light source directed at you, your iris will stop down decreasing your ability to see certain things. As an example, if you have a candle in a dark room, it would be easy to see it projecting its light. If you then took a large followspot and placed beside the candle and shined into your eyes... the iris of your eyes would close down causing you to be unable to perceive the candle. Is the candle suddenly projecting "black light"? No, it is simply being masked by the brighter light source.

You can not project true black light. As he shows... even with a projector, or gobos as described above, you're not projecting black. You're simply not projecting anything which results in the surface of the projection surface being illuminated with any ambient light in the room plus the spill light by aberrations from the light source itself.