Someone mentioned Goo rear projection spray in a recent post I can’t find back. The idea of spraying the pojection layer is very interesting. Does it really work, what are the positive or negative experiences. What should be the best way of using it (at the back, the front or in between the acrilat and the surface)

The product is discribed and sold on:

http://www.surroundsolutions.com/cgi-bin/surroundsolutions.cgi/100874.html

Ive used this in making my own projection home theater setup and the stuff is awesome for how cheap it is.  As for using it for a MT setup, it is a paint, so having an image be clear when it is projected from behind it probably wont work.  Just get some vellum or rosco grey, which is a projection screen and made out of paper/fabric so it can show an image through it well.

They offer a rear projection version of their product. If it can’t be used at the backsides because it blocks the infra red it can be used on the top as a combined projection and infra red blocker. I think I order half a liter and just try it out in the new year.

see http://www.goosystems.com/products/ at the buttom of the page.

I use the rear projection Screen Goo on my LLP table.  It works very well.  The Rosco grey looks a little better (slightly more contrast), but I found it blocks too much IR from my lasers.  I HVLP sprayed several coats onto 1/4” acrylic.  Also I find it easy to work with especially during assembly and maintenance.