Four Sketches of Comet C/2012 S1 (ISON), on its incoming trajectory spanning Oct-Nov. 2013, showing changes in the comet over time. Used a 20" F/5 Newtonian with 13mm Ethos, 35mm Plossl (Russell Optics), and 35 mm Deep View eyepieces. Drew filtered views in B&W on Strathmore tracing paper and a backlit tablet (LED Light Box app for i-Pad). Then stacked the filtered views to create colored drawings, where applicable. Used Photofiltre and Canvas for editing. Also used Baader Neodymium, Baader OIII, and Red filters.