Thanks everybody for all the kind words.
John, I painted the inside of the blank with white acrylic model paint. I didn't paint the tube at all.
On the light issue, I agree that they're too dark. I just got this light box set up last night, and I'm still playing with it. one thing that was recommended was white tissue paper on the sides and top of the box, but thinking that it would be too easy to mess up, I used white trash bags instead. I'll probably try the tissue paper next. That should lighten it up some. Another thing to try is going from the 60 watt equivalent CF bulbs to 75 watt equivalent.