Mask material

[smokeAndMirrors]

At the moment I'm controlling my lasers using DMX (Pangolin on the way!), but this means I can't have safety zones or attenuation maps for the beams (and one of my projectors is TTL anyway). I keep them for the most part above heads, but even tilting the projector at the stated max emission angle (30 degrees), I get a stray low beam on some patterns. So I read that you can just mask off the bottom of the laser aperture with a physical barrier. What material is this made from? Presumably black card would be a fire hazard?

[VJ AIWAZ]

i use this stuff and it works great

http://www.filmandvideolighting.com/blstforo12.html

[Andrew_D]

Look locally at a lighting supply house for Blacktak made by City Theatrical.
It's self adhesive heat proof tape and works great for beam masking, and controlling leakage of beams, etc.
2"x75' rolls. List price of 38.00 USD.