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Wavelength calibration

After having identified a few lines with the Identify window, click the \fbox{\tt Calibrate} button in the Main window. The Wavelength Calibration window appears. The associated parameters can be set and a preliminary wavelength calibration is performed on the central row YSTART by clicking on \fbox{\tt Calibrate}. The button \fbox{\tt
Edit} allows to remove calibration lines from the dispersion solution interactively, while \fbox{\tt Calibrate all} estimates the dispersion relation for the complete spectrum. The button \fbox{\tt Calibrate
twice} performs a two-pass calibration.

Results can be checked with the buttons located at the bottom of the Wavelength Calibration window. \fbox{\tt Dispersion} plots the dispersion relation, \fbox{\tt Residuals} plots the residuals, \fbox{\tt Spectrum} plots the lines identified during the calibration process. These three functions are by default performed on the central row of the spectrum. The button \fbox{\tt Line Shape} plots the residuals as a function of the Y-position for a line selected in a wavelength list.

Figure G.5: Wavelength Calibration window

Petra Nass