SADHAKA: the yoga of B.K.S. Iyengar is a feature documentary film about BKS Iyengar’s practice, life and influence from award WINNING director, Jake Clennell. Here is a link to an article about its filming- including a short trailer:

http://yogadork.com/2014/09/17/jake-clennell-on-filming-bks-iyengar-i-have-never-in-my-life-seen-such-an-expression-of-love-and-devotion/