Simple question really. In regards to lens hoods for standard DSLR/SLR lenses, is there a difference in picture quality if you use the soft rubber (the kind you can push in and pull out) type or the plastic type that usually come with the lens itself? Most rubber types are perfectly round where as the plastic types seem to have cut out's in them. Are there reasons for the plastic ones to have these designs instead of just being perfectly round?
Sorry for asking such a basic question, however, curiosity has gotten the better of me