Pillsbury's career spilled over into nearly every kind of application for photography. His career began in 1895 when as a student he documented in one hour with 60 different images the first fraternity rush at Stanford University. Pillsbury studied mechanical engineering at Stanford University and is credited with the invention of a specimen slicer (for microscopy) and a circuit panorama camera before leaving college. Two years later he invented the first circuit panorama camera and soon after took it to the Yukon to capture the opening of the mining fields and towns. By 1900 he had photographed many of the notable features of the Western United States.