Yes, you can paint any part of the uncoated side with paint (spray or roll on) that is designed for glass surfaces such Rust-o-leum UltraCover 2x or High Heat, which you can find at Lowe’s, Home Depot, or Walmart. Make sure there is still an area in the center for the camera to shoot through. The best color to use is black (blends in with unpainted area the best). Be sure not to use silver or white paint. Mask off the area you don’t want to paint with blue painters tape. Important: use only Scotch Edge Lock painters tape for best results. Press hard on the tape to ensure paint doesn’t get under it. Practice on a sample mirror first to make sure you’re getting the desired effect.