The North America Nebula. Taken at prime focus using a 152mm f7.5 AstroPhysics refractor on the back of an AstroPhysics 1200 mount. A one hour exposure on Kodak PPF 400 film, guided using an ST-4 autoguider with an 80mm f11. Celestron refractor This photo was taken in central Oregon, during August of 2K at our high desert (4000') astronomy cabin.