The distance above the image is (1) the distance below (1.6180). Right to left I left the margins constant with both square and horizontal images. With the horizontal images the overall paper shape is not to the Fibonacci ratio. With the square images the paper dimensions are in the 1:1.6180 proportion. I would be interested to see if you think it makes a significant difference using what is an imperfect application of the principle. (Click through)
Fibonacci