Well, I think that this is a somewhat bigger question to raise than meets the eye.
Literally speaking, in either case, i.e. reading a book and watching a film that is based on the book, it is the human eye that plays a primary role, although it plays the most important role in reading the book.
When watching the film, the sense of hearing is also involved.
Watching the film is a much more live experience than reading the book.
It is also faster, not leaving so much room and time for the brain to think, which is possible when reading the book, because you can take your time.
Personally, I enjoy reading the book more, because it is more original, while some films have been adapted and changed so much from the original that are essentially a different thing, sometimes with inconsistencies and inaccuracies.
yeah, good addition, thanks
it's really so - we don't have time to stop and think while watching the movie. We can press Stop, but it's different
and year, it involves hearing as well, and we have a ready made picture for our eyes
OMG, I made a big mistake in my comment: I totally forgot audio books, which are based on the sense of hearing!