code: def vignettingFromDifferentObjects(imgs, bg):
      '''
      Extract vignetting from a set of images
      containing different devices
      The devices spatial inhomogeneities are averaged
  
      This method is referred as 'Method C' in 
      ---
      K.Bedrich, M.Bokalic et al.:
      ELECTROLUMINESCENCE IMAGING OF PV DEVICES:
      ADVANCED FLAT FIELD CALIBRATION,2017
      ---
      '''
  
      f = FlatFieldFromImgFit(imgs, bg)
      return f.result, f.masf vignettingFromDifferentObjects(imgs, bg):
      '''
      Extract vignetting from a set of images
      containing different devices
      The devices spatial inhomogeneities are averaged
  
      This method is referred as 'Method C' in 
      ---
      K.Bedrich, M.Bokalic et al.:
      ELECTROLUMINESCENCE IMAGING OF PV DEVICES:
      ADVANCED FLAT FIELD CALIBRATION,2017
      ---
      '''
  
      f = FlatFieldFromImgFit(imgs, bg)
      return f.result, f.mask
docs: Extract vignetting from a set of images
      containing different devices
      The devices spatial inhomogeneities are averaged
  
      This method is referred as 'Method C' in 
      ---
      K.Bedrich, M.Bokalic et al.:
      ELECTROLUMINESCENCE IMAGING OF PV DEVICES:
      ADVANCED FLAT FIELD CALIBRATION,2017
      ---