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I am facing problem with the background sky subtraction while extracting
spectra using apall.I find that the night sky emission lines are not well subtracted. I am
currently using V2.12.2. However, I did not face any such problem when I
was using V2.11. I have attached with this mail samples of spectra extracted using V2.12.2
(mcneil_new.fits) and V2.11 (mcneil_old.fits). The improper subtraction of
the OH night sky emission lines is very evident in the first half of the
spectrum, which corresponds to wavelength regions beyond 7600 A. I request your help/suggestion in this matter.Regards,G.C. Anupama

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Dr. G. C. Anupama
Indian Institute of Astrophysics Ph: +91-80-5530672 Ext 344
Koramangala, Bangalore 560 034 Fax: +91-80-5534043
India e-mail: gca@iiap.res.in
gca@iiap.ernet.in http://www.iiap.res.in/personnel/gca/gca.html
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