Also, I refuse to believe that there hasn't been a power cut in that building over the last 52 years. Power cut = Film ends!!😬😂.
Discussion
Fear not:

So, it wasn't even "Filmed" then🤔.
It is a film.
film.
the screening is the slow yellowing, cracking, and fading of the paint, a change imperceptible in short viewings but evident over years.
in this way, one can observe all paintings as film over a long enough time scale
pigments degrade over time
Well, I suppose, but conceptually this is presented as a 'film', most paintings are not. But you could argue the case :)