I'm trying to get some more knowledge on this whole lighting thing. I'm somewhat aware of the basics of bouncing and all that, but I'm trying to figure out when the time is right for a diffuser like the plastic cap that goes on my sb600, or a bounce card (which I just made a nice on out of that foam paper stuff you get at the craft store). I've never even really given any though to gels, but I guess their use is pretty obvious: to either mimic your ambient light for more even tones, or for a special effect. Basically, I'm looking for some basics on using flash outside of the basics (if that makes sense).