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Rebin to wavelength scale

After completing the wavelength calibration, the \fbox{\tt Rebin...}button in the Mainwindow allows to rebin spectra to wavelength. The Rebinning window offers three methods: linear, quadratic, or spline transformations. The first two provide flux conservation. The spline option does not incorporate a detailed conservation of flux. The button \fbox{\tt Rebin rbr} activates the row-by-row solution corresponding to the MIDAS command REBIN/RBR. The button \fbox{\tt Rebin 2-D} resamples by a bivariate polynomial solution and activates the command RECTIFY/LONG. The 2-D solution has been generated by the wavelength calibration process only if the option ``Compute 2-D solution'' in the Wavelength Calibration window has been selected before calibration. The button \fbox{\tt Rebin table}allows to generate a table as output format and therefore avoid to resample the data. This table can be plotted with the button \fbox{\tt Plot table}.

Clicking on one of the Rebin buttons pops up a list of .bdf files in the directory. Click the name of the selected file. A small prompt window appears requesting the name of the output file. The default is the input file name with the suffix _reb. The button \fbox{\tt Plot table} uses the name of the output table generated by \fbox{\tt Rebin table}.

The rebinning processes use the Starting, Final wavelength and Step parameters defined in the Rebinning window. If these parameters are not given, default values derived from the wavelength calibration coefficients are used. The progress in the rebinning process is reported in the MIDAS window.


  
Figure G.6: Resampling Window


next up previous contents
Next: Extract Up: Getting Started Previous: Wavelength calibration
http://www.eso.org/midas/midas-support.html
1999-06-15