My first encounter with P&P was seeing the P&P2 film.
When you read the book, you become aware of how much extra there is in the film, not in terms of dialogue, but in terms of the entire atmosphere that the film supplies.
Even quite short scenes in the film, can lend a lot to one's perception.
I'm thinking of scenes like the Bingleys and Darcy arriving by coach at the Assembly Room, with runners carrying lighted torches, running before the coaches. That is a memorable sort of scene.
Various dances, at different venues, form a decent chunk of the first episode. In the book, you don't get much sense of what all of this is like. Seeing the dance routines, and everyone dressed up, and hearing the, slightly unusual, but very catchy, music, makes quite a contribution to the film viewer's perceptions.
Take even a very simple thing like the beginning of Chapter 4: When Jane and Elizabeth were alone.... In the film we have the two girls leisurely strolling through their garden on a sunny afternoon picking flowers. Whoever would imagine that it might be like that from reading the book.
I wonder how someone who has read the book, but has not seen P&P2, imagines all this.
I cannot conceive of myself imagining the scenes, or indeed the characters themselves, in any way other than how P&P2 depicts them.