Re: Strange result


R L
 

It is a flat defect as I suspected (see the feature in the flat at ~380,470)
I don't know why the flat has not corrected it though. You could try  running the data reduction with and without the flat correction to see if it working. (What software are you using ?)

Cheers
Robin
--
www.threehillsobservatory.co.uk
Celestron C11, EQ6, ATIK 314, 428
Star Analyser 100,200, ALPY 600,200 LHIRES III Spectrographs

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