Notice 
1) Limited Mag Zero Point / Sky Mag data points which are generated for C filter image 
  (majority of session was in V & B filters)
2) Increase in airmass as RR Lyrae moved from 64 deg altitude down to 21 deg altitude
3) Fluctuations in FWHM due to heating interior of dew shield with hair dryer to clear dew. 

See explanation of these graphs