Click on the image to view the enlargement.
If you look really closely to the upper right hand corner you'll spot the faint outline of the double rainbow directly above the first one. Had I realized both would show up in the photo I would have taken photos of the second one as well.
This photo was taken with my old camera... My new Panasonic camera could have got this shot in one take. My Canon Powershot? Not so much. I had to take 2 side by side photos then paste and blend them together to get the entire rainbow into one image.