According to Pennebaker , RCA had sent him to film part of the show as a promo for a new video disc product the company was developing .
Pennebaker had originally intended to film a few songs for approximately 20 minutes .
According to Pennebaker , RCA had sent him to film part of the show as a promo for a new video disc product the company was developing , and he had originally intended to film a few songs for approximately 20 minutes .