Does this film have any real cinematic merit?

Okay, I love it, but then I love every performance and recording of "The Magic Flute" that I've ever seen. It's a bulletproof show, always utterly enjoyable no matter now silly or serious the production may be.

But does the Ingmar Bergman "Magic Flute" have any merit as a piece of film, rather than just a recorded opera? Did all the critics rave over it because of Bergman's name and history, when it has no more merit than any other video of an opera, or were the critics right about it being a remarkable piece of cinema in ways I never understood?