Sharpness usually isn't the problem, unsharpness (bluring) sometimes is :)
Printable View
have you tried doing a bitmap copy of the final art, then messing with the blur/sharpness slider in the photo tool?
As a slight mod, you could do a bitmap copy of just the background, then blur that... Not sure how deep you need your depth of field.
very good.
can you imagine a drawing?