I think I originally saw this when it aired on PBS.  I may have missed the beginning, but it was so good, that I had to track down my own copy. What makes this documentary so good is that it really gives you an insider's look at what went into making these early albums.  It also has some moving personal moments, such as when Phil Lesh desribes his father's illness in relation to the song, "Box of Rain".  This is a must-have for any fans of early Dead.