In general, following each instrument intervention, a full complement of calibration frames (darks, flats, wavelengths, linearity, distortions, fibre-fed HCAO, telluric standard star, PSF star, and pupil images) are obtained. A multitude of parameters for each of these calibrations are scored and compared to their values prior to the intervention.

• Instrument dismounted
  
  2011-03-16 to 25: SINFONI was dismounted from UT4 to repair the issue of attenuated light in MACAO. No intervention on the instrument itself was done.

• Mirror recoating
  
  2009-09-12: The primary mirror (M1) of UT4 has been re-coated. SINFONI returns to operations.
• Earthquake
  
  2008-05-06: No adverse effects found in SINFONI.