No need to ask before you use, but:
1. Link to this image or my profile in your artist's comments.
2. Leave a comment on this image with a link to the image you created. (I want to see them!)
3. Ask before you submit it as a print. (I have to make sure you didn't just desaturate it or something ridiculously simple like that.)
4. Please do not use this in pictures I would be embarrassed for my grandmother to see.