I had a question from an author who has a bit of a track record in one genre but now wants to write a book in a totally different genre. She is finding that her publisher is resisting offering something different from what her readers will expect from her.
One option is using a pen name for the new genre. Of course it does mean that you have to build a whole new audience, but at least you won't lose fans of your original type of book.
The fact is that readers (just like publishers) generally do pigeon-hole authors and when they find one they like, they want to see more of the same. By creating a new identity you may be able to skirt this problem. Of course this can work for artists, photographers, and anybody else, too.
(Flexibility and creativity are the most valuable tools you have--and for some fresh ideas on how to be even more creative, get my newest book, "Creativity Now," published by Pearson.)