portrait of an artist

I love this picture.
I know this is your image, but would it be okay if I drew it? Not for commercial purposes, but simply for practice in my sketchbook, and possibly a painting/drawing for my own collection?
When (or if) it's complete and posted here on dA, I'll give you full credit for image, link included in the comment space.

If it's not okay, I won't, but I would really love to!