It took me about a week trying different ways to get a decent rainbow out of it but today I have the picture on the wall about 3 meters in front of me in full daylight. , so not bad at all. I'm excited to see what I can achieve in a week or two. The second image shows how the light and prism line up if you want to try to reproduce this. The glass looks and feels amazingly durable and comes in a beautiful box. You really can't go wrong with this.