How to take imaging flats with the internal lamp

• Be sure the dome is dark

• Set up spectrograph in Lucifer ONE Control Window

      Select filter

      Grating = Mirror
 
      Camera = N 3.75

      Mask in turnout

      Collimation Unit IN

      Turn on the HALO3 Lamp

• Set # exposures, NDIT=1 in Lucifer Readout Control

• Exposure times: 6 sec for J, 5sec for K, 4 sec for H