The very first thing to know and remember is — “Never touch or pick up another musician’s instrument without asking permission. The owner of the instrument has the right to say No.”
I raised the question at a musicians’ website about the ethics of filming or recording a band or practice session. A hot discussion developed, with some advocating courtesy and requesting permission for recording a practice session, and others who didn’t care. There was general agreement that filming/recording a public performance is to be expected in these days of instant video capability, etc. Of course, copyright violations could be involved.
The videos on the google group page for the Flipside Coffee Shop Jam that I host are used with permission.
In researching this question, the first sites I found talked about legalities. Most of these legal issues concern professional bands and professional videographers. See:
http://www.desktop-documentaries.com/copyright-issues.html
“When making a film, you must respect copyright of other artists when you want to use their music, video, film, artwork, photographs, etc. You MUST have their permission and/or pay to copy their work.” and
“The best and easiest thing to do is get permission before filming begins. It’s a HUGE hassle to track down people later.”
Then I started a thread at the Mandolin Cafe website that concerns amateur musicians and random camera/phone users. You may find the many experiences and viewpoints expressed here:
traditionsstringband.net 