I've tried twice now to watch Solaris and fell asleep both times - someone let me know if it's worth it! I've seen every other Tarkovsky film and love his work, this one just felt particularly difficult for me.
I find it so relaxing that I’ve just learnt to enjoy the whole experience and enjoy the dozing as part of the experience of watching the film.
You have to allow yourself to be immersed in it. It's a slower pace than commercial film makers adopt, but the atmosphere builds.
Or mimoids.