A revision of the analysis of the previous campaign spectra has now led to the use of the equivalent width (EW) of the red and blue components for the determination of the baseline.
See: http://www.bav-astro.eu/index.php/veraenderliche/bedeckungsveraenderliche/vv-cep-kampagne
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In view of the immediate imminent eclipse, a well-defined base line now appears for both, the peak height and the EW. At the upcoming OHP spectroscopy session in the last week of July, we will try to improve the quality of the baselines by further observations.
Ernst Pollmann