Correction of solar dopplergrams' large-scale flatfield" . Patrickeyev I.A., Mashnich G.P., Khlystova A.I., Zhang H. The authors have proposed and compared three different methods of large-scale flatfield correction (time averaging, Fourier filtering, and wavelet-based filtering). ... Patrickeyev I.A. - Institute of Continuum Mechanics, Russian Academy of Sciences, Korolyova 1, 614013, Perm, Russia; e-mail: pat@icmm.ru . ...