I was watching ESB again and I noticed something. Sometimes when the angle of a scene changes, there's either a dark or light strip on the bottom of the end frame of an angle or the top of the beginning frame of one. To me it looks like some sort of glue used to stitch the film together; whenever it happens, it only lasts for a frame.
Did you want to know about these, dark_jedi? They're barely noticeable and I don't really think a necessary fix.