I've been asked to help design Alice in Wonderland, but the director wants to use blicklight to make the cat appear and dissappear, I'm cool with it and all but my question is what gel would I use to get the blacklighteffect? any advice or recamendations would be great!
Hmm...first, unless all of the other lights are out on stage, this will not work, unless it's just painted on to a surface and the blacklight is used to make it appear on that surface (wall, box, etc). It will not work if the cat is a physical object. Now that I've covered the way too obvious which you probably already knew...
Get blacklights. Don't use gel, get the real thing. If the director wants it that much, they're gonna have to rent or buy. If you're in DC, it should be easy to find a place to rent Blacklights.
I think that the question that you should ask is "how much UV will tungsten bulbs put out anyway?" and I can't answer that...but I still say go with the real thing! Get an Altmanunit on rent or something like that.
Do a search for a thread on here, I belive it was title "Yikes! stripes".
There was a very long and deeply moving discussion on all aspects of using UV light onstage. It is not necessary to completely blackout the stage of other sources of illumination, but the amount of other light < or rather the amount of visible light> is going to greatly impact the size and type of UV fixture you use. I don't still have the Roscogelbook memorized but I do remember a couple of colors that were darn near a uv filter, however you needed to be using something like a carbon arc or similar source of light that supplied plenty of UV anyway. Hope that helps.
As van was saying, its very hard to get UV light out of a conventionalfixture. The glass has been blown with UV filters first of all. Doubled up R85 works fairly well. Woods glass also does it. But really the best way to go is a dedicated UV fixture.
Take a look at Wildfire's blacklights and blacklight related gear at http://www.wildfirefx.com. They make lights and paint and all that good stuff. You can probably rent their fixtures at most renal houses, and they work very well.
I did the scene in "Once Upon A Mattress" where the Jester and the Jester's father are dancing the old soft shoe with Black Light . The Father is a ghost so I put him in a white tux and rented a Black Light cannon that I used to light a very specific area of the stage. It worked pretty well but you've got to keep your areas well separated and you have to rent some real firepower if you want to do it right.
Here is a thread I started a while back that has a discussion about the different types of UV producing instruments (it gets a little side tracked but there is some good info there). Also look up that one Van mentioned about stripes.
And yes, Wildfire probably makes the best UV gear but it'll cost you. You'll be amazed how much a quart of paint costs.