Hello everyone! I found this DIY matte box for the DVX100 (http://www.desktopcreations.com.mt/dtc_shade/) and it says to use A3 sheets of hard card in the construction. I was wondering what exactly this was and if anyone knew where to get it. I'm assuming it's not regular old construction paper as it looks a fair bit sturdier. The guy at my Home Depot didn't seem to know what I was talking about. Thanks!