It is also difficult to articulate the subtleties in cinema, because there aren't words or metaphors which describe many of the emotions you are attempting to evoke.
You have to understand the nature of light.
The sun is the most parallel light source because it is so far away.
I hope I'm still shooting when I'm 80.
You are always a student, never a master. You have to keep moving forward.
The audience has to understand that if the film is going to have any meaning for them. If they are going to empathize with the characters, they have to visualize the process of concentration involved in making every move.