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Extracting the Spectrum

 

The limits of the object are defined in the keyword . A simple row average is performed by:

Midas...> SET/LONG OBJECT=189,196
Midas...> EXTRACT/AVERAGE corr56 ext56

which is equivalent to the general MIDAS command:

Midas...> AVERAGE/ROW ex56 = corr56 @189,@196

An optimal extraction algorithm is also available, requiring the knowledge of the CCD detector parameters, a preliminary definition of the sky background, as well as the values of a polynomial order and a number of iterations . The command:

Midas...> EXTRACT/LONG ccd0056 ext56 sky56

applies the Horne's optimal extraction algorithm to the image ccd0056.bdf and performs the sky subtraction to generate the output image ext56.bdf.



Pascal Ballester
Tue Mar 28 16:52:29 MET DST 1995