i like your idea dannat, unfortunately there's cloud hanging around and my next month is pretty busy with working and flying around, but it's definitely going on my 'must do' list!
thanks guys, the weather was pretty tempermental friday night, so i was only able to be set up for a few hours, and this wasn't taken long after focusing... goes to show that it wasn't pefect!
are there any focusing aids that i can use to help me reach focus?