Hmm here is a thought, move the plane back, add another plane with glass material, and ad light between the glass and the outside image. I never tried that but, hope that works!
I tried that and I think it will work, but now Yafaray wont render the scene Every time I disable the texture that is causing the problem, the next texture comes up as the problem. I tried appending it with no luck. It’s also just this file.