After reading this post, I thought well huh. That’s fucking easy. Roscolux filters? I work with those all the time. I can get scraps of those specifically even. I can get the swatch books, up 10 of them, free! Every time I order from them, which 4 to 5 times a year.
Maybe someone who is more knowledgeable about light than myself can verify if this checks out or not. If this is a viable PAR meter at this price? I’m happy to build that. Hell, I’m happy to build a few.