DSLR Transformation Coefficient
I have been trying to determine the Transformation Coefficient for my Canon 20D camera, so far, unsuccessfully. I recently came upon DocArne's explanation of the procedure and compared it to Des Loughney's paper on the same subject. I noticed what seems to be a significant difference in the two methods. Where Arne's magnitude term is the the Instrument Magnitude of a star minus the Standard Magnitude, Des' magnitude term is the Observed "Difference" in magnitude of a pair of stars (OD) minus the Estimated (tabulated) "Difference" in magnitude(ED). Is there an actual difference in these procedures or are they mathematically equivalent?