>> However there is nothing >> in the scales published (1-5 or 1-10, Pickering or others) definitions or >> explanations, that says hey wait you have to knock off a couple points for >> having a small scope. These scales were made FOR small scopes. That's why you avoid these arbitrary scales altogether, and use physical units you can actually measure, specifically arcseconds. \Brian -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list.