Quote Originally Posted by ac12 View Post
I googled "rubylith" since I heard about it. But it turns out that is a film, not a hard piece of plastic. So it would be tricky to put into the filter holder w/o something to hold it from sagging.
Just for the record, Rubylith has a slightly frosted finish to it, so it would be a bad candidate for transmission filtering.

Here's an off-the-wall idea, though. How about getting one of these sampler filter booklets for free (plus $7.50 s&h)?

Rosco Swatchbooks

Then have a glass shop cut you a small piece from scrap and attach the correct filter to it. Either with black tape around the edges, or a lightly-applied clear spray adhesive.