I was wondering how to tell dual-layered discs from single-layered? I read the offical DVD FAQ, and it says that you can look at the gold color on the disc. Well, the problem is that this method only works on R1-discs. I have checked quite a few R2-discs which I know for sure is dual layered, but they don't have the gold color. So how can I tell one from another if I can't spot the layer change?