I took this picture of an exquisite pair of sun connures in a bird park in Bali during my Indonesia photo tour. They were in a cage with a wire mesh background, and I had to shoot through wire mesh to get the shot. The foreground mesh disappeared because I used a medium telephoto lens with a lens aperture large enough (f/8) to make it disappear due to shallow depth of field, but the background mesh looked terrible as you can see below.
To eliminate the ugly background, I opened another photo of out of focus foliage. I then cloned the soft, green foliage to the bird picture. I covered the background with the clone tool set to 100% opacity, but when I came to the edge of the birds, I lowered the opacity to 70%. This helped me blend the out of focus greenery with the edge of the connures in an attempt to make this look completely natural and, at the same, retain the detail in the edges of the feathers.