I printed photos on the ink jet transparencies, cut them in circles and inserted them in the clear ornament balls. They look like bubbles but they are hard to see, like you said. I even tried darkening the photos before printing but it didn't help too much.

The images are too hard to see if you dont do something to the back side, unless you are just hanging one from an ornament stand or somewhere where you have a clear view.
I sprayed silver paint on the back of mine. White crystal glitter can also work if you do not have too much small detail in the image.

Karen

I'm going to try printing on the silver metallic film to insert in the balls. I'm just wondering how to make it hold its shape. I'm afraid it will stay curled, as it's not that thick. Any ideas?

Silver metallic film? I have not seen this in person so I don't know how thin it is, but it has to be a certain thickness not to get jammed in the printer. So I think it should relax inside the ball & straighten itself out.
The trick might be to get the size just right...a hair smaller than the inside of the ball, so the glass would help keep the image in place and prevent curling.

The silver metallic film is really cool! It looks like printing on a mirror. I bought a package a year ago and haven't used it very much. I printed out a picture of my son and his date for the prom and it looks really nice. I think if it will hold it's shape in the ball that it will look very unique. I've got a wild weekend coming up, but will try to find time to make one and take a picture to post here.