Prime Keys are:
	CAMERA
	T_OBS
	HMI_SEQ_ID_FOCUS
DB Index Keys are same as Prime Keys
All Keywords for series hmi.offpoint_flatfield:
	TELESCOPE 	(string)	[TELESCOP]SDO/HMI
	CAMERA    	(int)	[CAMERAID]Camera ID
	T_OBS     	(time)	[T_OBS]Observation time
	HMI_SEQ_ID_FOCUS	(int)	[FOCUS_ID]Focus ID
	INSTRUME  	(string)	[INSTRUME]HMI_SIDE1 or HMI_FRONT2
	FSN_FIRST 	(int)	[FSN_FRST]FSN of first offpointed image
	FSN_LAST  	(int)	[FSN_LAST]FSN of last offpointed image
	FSN_INPUT 	(string)	[FSN_INPT]FSN list
	PZTFLAG   	(int)	[PZTFLAG]1:PZT flatfield, 0: large offpoint flatfield
	DATE      	(time)	[DATE]Date_time of processing; ISO 8601
Segments for series hmi.offpoint_flatfield:
	offpoint_flatfield	   none	   fits	4096x4096	0