Data runs

The sum of the data taking time of all data runs of the night with less than 30min calculated as the difference between the time stamp of closing and opening time of the run.

All runs

Same as Onle data runs but including all other run types such as pedestal, drs calibration etc., which have a source name set. This is usually the case if the telescope is tracking a source during the run. This does not include times as repositioning times when the no data acquisition was active.

First-to-last

This is the time difference between the end time of the last run of the night and the start time of the first run of the night. This corresponds roughly to the time the telescope is operated and is a measure whether startup and shutdown was properly scheduled.

Twilight

This is the time of astronomical twilight which - in the ideal case - corresponds to the maximum data taking time.

On average 42% (10h) of a night is twilight. So a data taking efficiency of 50% twlight means a total duty cycle of 21%.

SELECT
   fNight AS '0',
   TIME_TO_SEC(TIMEDIFF(fStopObservation, fStartObservation)) AS '1',
   TIME_TO_SEC(TIMEDIFF(MAX(fRunStop),MIN(fRunStart))) AS '2',
   SUM(IF (TIMEDIFF(fRunStop,fRunStart)<'00:30:00', TIME_TO_SEC(TIMEDIFF(fRunStop,fRunStart)), 0)) AS '3',
   SUM(IF (TIMEDIFF(fRunStop,fRunStart)<'00:30:00' AND fRunTypeKey=1, TIME_TO_SEC(TIMEDIFF(fRunStop,fRunStart)), 0)) AS '4'
FROM ObservationTimes
LEFT JOIN RunInfo USING(fNight)
WHERE fNight<DATE_FORMAT(DATE(NOW()), '%Y%m%d')
GROUP BY fNight
ORDER BY fNight

[3]< 0 : Array ( [0] => 20130526 [1] => 29747 [2] => 23988 [3] => -632 [4] => -1895 )
[4]< 0 : Array ( [0] => 20130526 [1] => 29747 [2] => 23988 [3] => -632 [4] => -1895 )
[4]< 0 : Array ( [0] => 20130527 [1] => 29681 [2] => 24456 [3] => 699 [4] => -3930 )
[3]>[2]: Array ( [0] => 20130808 [1] => 31734 [2] => 53369 [3] => 31878 [4] => 26677 )
[3]>[2]: Array ( [0] => 20131003 [1] => 37694 [2] => 75739 [3] => 38229 [4] => 29939 )
[3]>[2]: Array ( [0] => 20131006 [1] => 37995 [2] => 72045 [3] => 38466 [4] => 29905 )
[3]>[2]: Array ( [0] => 20131009 [1] => 38291 [2] => 40829 [3] => 38666 [4] => 30503 )
[3]>[2]: Array ( [0] => 20170711 [1] => 29451 [2] => 32385 [3] => 30464 [4] => 26627 )