What with all the buzz about the movie adaptation for The Hunger Games being underway, I've been wondering -- how do authors react when they learn their book's being adapted? Sure, in one way, it'd be great, as a measure of success and a way to attract more readers and all. But what about when the movie doesn't live up to the book?
Usually, when a book's converted into a movie, you get a group of people happy with it, and a mob of disgruntled readers. I've been one of those readers several times over (They gave Annabeth dark hair? There's no unicorn in Inkheart!), as I'm sure most every has. So for the author, it makes sense to assume that it'd be much worse.
I really think that it's all about how you handle it, though. If you go into things, deciding beforehand that it's going to be different from the book -- maybe something else entirely -- then you'll probably fare much better. And have more hair when it's all through. This is someone else's interpretation of your darling -- isn't that cool in its own right? Seeing something through someone else's eyes, seeing how your words, your worlds, characters, inspired someone and took shape in their head?
Once I read an interview with an author -- I think it was Cornelia Funke, but it was several years ago, I can't find the interview now, and I've slept since then, so I can't be 100% sure -- and a question came up about a movie based on the book the author had written. (Again, I'm fairly certain it was for the Inkheart movie.) The question was about how different the movie had been from the book, and the author said something to the effect of not really minding, because, "The movie isn't mine. It's the director's project, so I just view it as something else completely."
Even though I can't link to the interview, though I can't promise if the author was Cornelia Funke, and I don't have a direct quote -- it's the same basic principle, isn't it? The movie isn't yours. Distance yourself from it.
Anyway, you can worry about all that after you've finished the book, gotten it published, hit it big, and gotten a movie in the works. And for most people, that's still far enough away to have plenty of time to worry about it later.