Thanks, Laura... I'm working on using my seamless backgrounds and editing in post-production, in this case, vignetting around my subject(my son). I haven't really mastered it yet, and what I'd really like to do is some of this effect "in-camera" with my lighting setups. If I have to enhance slightly in post, that's okay, but this vignette effect was done completely in post.
I agree the background is dark -- I'll keep practicing. :)