I am going to first admit that I don't know anything about flash photography, but I DO know that I feel limited without one and am ready to make the jump. My husband is getting me the 580 EX II for my birthday next week, but I was wondering about diffusers. I see most are around $15...pretty cheap, but then there is the Harbor Digital Design "Ultimate Lightbox Diffuser" and it is over $100. Could someone tell me if a "lightbox" as opposed to a "diffuser" makes that much of a difference on the end of a flash? Is the lightbox meant to be attached to the flash when it is on the camera or is it something for when you are shooting in a studio setting, off camera? What do YOU use?? Thanks so much!