A Demonstration of Accurate Wide-field V-band Photometry Using a Consumer-grade DSLR Camera
Department of Physics and Astronomy, University of Denver, 2112 East Wesley Avenue, Denver, CO 80208
37 C rue Charles Dumont, 21000, Dijon, France
Vogelbeerweg 34, 31515 Wunstorf, Germany
Physics Department, University of Crete, GR-71003 Heraklion, Crete, Greece
1525 Beachview Drive, Virginia Beach, VA 23464
Received May 8, 2012; revised July 3, 2012; accepted July 3, 2012
The authors examined the suitability of using a Digital Single Lens Reflex (DSLR) camera for stellar photometry and, in particular, investigated wide field exposures made with minimal equipment for analysis of bright variable stars. A magnitude-limited sample of stars was evaluated exhibiting a wide range of (B–V) colors taken from four fields between Cygnus and Draco. Experiments comparing green channel DSLR photometry with VT photometry of the Tycho-2 catalogue showed very good agreement. Encouraged by the results of these comparisons, a method for performing color based transformations to the more widely used Johnson V filter band was developed and tested. This method is similar to that recommended for Tycho-2 VT data. The experimental evaluation of the proposed method led to recommendations concerning the feasibility of high precision DSLR photometry for certain types of variable star projects. Most importantly we have demonstrated that DSLR cameras can be used as accurate, wide field photometers with only a minimal investment of funds and time.