I found a great graphic and I read the artists terms. They asked that no alterations be made and that a credit link be placed on the pages. I was carefull not to change the graphic and added a pretty frame and made it into a background. I was so proud of it. Then the artist contacted me an accused me of altering it and told me that this derivative work was an infringement of their copyright.
Lets start off with what Derivative works are.
Derivative something derived. Derived to take, receive, or obtain especially from a specified source. So if you take any part of a graphic, writing, or music composition and change it or make something else out of it, you have made a derivitive work. You couldn't walk into an art gallery and start carving a new face on a sculpture to make it look better. So how do you keep from making an error and how do you know.