Okay, here are some more experimentation resultsâ€¦
I was at a local art store and saw that they were having a sale on acrylic paint, so I said what the heck and bought some to try it out. I have a blackout screen with no treatment whatsoever. I thought about painting it with a Rustoleum Silver, but my test on a foam board was very uneven, so I gave up on that idea.
What I really wanted to do was to duplicate what Ddog was recommending, but since I donâ€™t have a sprayer, so I tried to roll it on. I first bought a white base â€“ Golden Acrylicâ€™s Titanium White (1 qt) â€“ the whitest white I could find. The store ran out of a silver pearlescent (dang!), but they had a tube of Golden Acrylic pearl with â€œfineâ€ pearlescent, so I decided to give that a try ($22 total).
First, the acrylic paint was too thick, so I thinned the white with about 25% water. I laid two even coats with a small foam roller. After the paint dried, I checked it out. Colors were better, but blacks were worse and any ambient light had much greater effect on the screen than without the paint. Disappointing since I heard so many good things about Gesso on blackout screens and I figured this should give pretty much the same result.
I moved on to applying the pearl paint. I had some glaze sitting around, so I poured about a qt of glaze and mixed it with the entire tube of the pearl paint. I mixed it thoroughly and painted three coats of the paint. Like I said, Iâ€™ve tried the Rustoleum Silver before, and that gave me a really bright screen with fantastic blacks (but horrible finish), I was hoping for something comparable to that. The finish was fairly white (but at lower temperature than titanium white), but definitely had silver sheen to it. The pearlescent flakes were much finer than the Rustoleum Silver, it almost looked like some of the more expensive screens I have seen.
The result is not bad at all. The screen is significantly brighter (not as much as silver, but noticeable), the contrast has improved slightly, color is also sharper, and black level is at least what it was with the plain blackout cloth. Definite improvement from what I had before. Only negative is that during a bright scene, I can see some of roller marks. Overall I am happy with my $22 and sweat equity investment.
Now, I am trying to decide whether to lay down two or more coats of clear glaze. I know Ddog recommended those steps, but I am apprehensive about giving it more sheen that what I have now. I may try a coat and see what happens.