Mm, I visualize every scene too, but I do it all in my head. Your approach seems like hard work to me. :) I also have a tendency to play out scenes in my head as if I'm watching it in a cinema or if I'm actually in it. (though I swear I don't Mary Sue)

Same happens when I read a book. I often think back and can't remember if I've seen the film or read the book.

But I do have a tendency to walk by things in shops and know I'm going to write about them some day. When that happens I bring them home and put them on the shelves in my study. It's like Ye Olde Curiosity Shope now. :)