Although rating the quality is highly subjective I'll attempt to describe my system
Excellent Plus - Highest quality possible until it is Digitally Enhanced (Improved with computer technology) Excellent - No problems - probably the best available Very Good - May have a glitch here or there Good - May have some minor problems that hopefully are noted Average - Has problems that should be noted Embarrassing - It's probably rare
Another Term used is "Considering the Age" Usually when this is used it refers to a very good transfer from some sort of film Not today's DVD quality but probably the best available till Digitally Enhanced