This is a composite of seven individual photographs taken on the same day. The shoes taken through glass at a shopping complex (100mm macro hard against the glass) and photos taken of $100, $50, $20 notes flat on a dark background. Notes were then extracted from their background, sized to fit and then warped, copy/pasted onto themselves multiple times.
Multiple layer/Masks were used to set shadows on each note to represent the appropriate lighting directions.
Shoes were then extracted from their more complex backgrounds, sized to fit. pasted onto note and rotated and warped slightly to fit direction of light. All shadows were then drawn with a combination of lassoo tool/mask/levels/blur tool.
As each layer was completed it was merged down to reduce the memory requirements of PS. Estimated about 5 hours of tedious work, but fun and good PS practice.