A concise method for reducing photographic spectrograph calibrations

An accurate and concise method of fitting and presenting photographic spectrographic calibration data has been developed that overcomes the shortcomings imposed by polynomial fitting techniques. This approach utilizes hitherto ignored correlatible data from neighboring wavelengths to increase the accuracy and smoothness of data at each particular wavelength. The results empirically confirm the assumption that an over-all system H-D curve at one wavelength can be accurately mapped into the H-D curve at a near wavelength using only a scaling constant Agamma and a translation constant Bgamma. This method also allows extrapolation beyond some of the raw data calibration ranges.