Almost stepped on this Pigmy rattler in Eastern Tennesse.
I thought the position of the snake lent itself to the circles theme.
I applied curves to increase the contrast; upped the saturation by +10; used a Gradient Fill layer: radial-reverse-scale 150 then changed the blend mode to Difference to reverse the outer edges to give a negative look; used Nik Sharpner and brushed sharpening just on the central portion.