I first saw this film at the Royal Festival Hall London in the early 70s and subsequently have owned it both on VHS and now DVD. I should admit right away that Dame Elisabeth is my all time favourite soprano and I never missed one of her RFH annual lieder recitals. This film was studio produced concurrently with a very successful Salzburg Festival production and so it captures much of the naturalness of a live performance. Cinema buffs may find the filming rather dated but for opera fans the spectacle of the greatest post-war Marschallin accompanied by one of the best casts available at the time is a truly life enhancing experience. The Monologue is just about as perfect as one could imagine and the humour and pathos of the last act is never heavy handed. There is no opera film more important to me and it would certainly be my Desert Island choice.