>>3193261>>3193246This one uses the 500mm mirror lens, zoomed way in on the magnifying lens from about 10 feet away. This isn't cropped, but it is rotated and the saturation/vibrance are upped a good bit. Having the subject backlit helps a great deal in pronouncing the effect.
Using a larger glass magnifying lens would make it easier to get more in the frame and have less cropping.