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chara:classic_guidelines [2018/01/29 19:50]
127.0.0.1 external edit 		chara:classic_guidelines [2018/07/05 08:56] (current)
jones
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 +====== Classic Guidelines ======
 ==== Guidelines for Selecting Observing Settings for Classic ==== ==== Guidelines for Selecting Observing Settings for Classic ====
 \\  For stars brighter than K < 5.5 mag, use destructive mode.\\  For stars fainter than K > 5.5 mag, use non-destructive mode if needed.\\ \\  If possible, stay at 750 Hz so that the noise peaks are furthest from the fringe window.\\ \\  If recording in non-destructive mode, check for saturation on the brightest target in the observing sequence. Saturation occurs at a sum of ~ 300 counts (150 counts per pixel). If the sum of counts is close to 300, then click the "DIFF/SIG" button on the CLASSIC GUI. Saturation occurs when the signal in the DIFF/SIG window flatlines at the end of the scan (maybe we can get a screen shot to show what saturation looks like). If the signal is saturating, then you need to record at a faster (higher) rate.\\ \\  You don't have to worry about saturation in destructive mode.\\ \\  To determine the best camera speed, go to the faintest star in the bracket:\\  \\  For stars brighter than K < 5.5 mag, use destructive mode.\\  For stars fainter than K > 5.5 mag, use non-destructive mode if needed.\\ \\  If possible, stay at 750 Hz so that the noise peaks are furthest from the fringe window.\\ \\  If recording in non-destructive mode, check for saturation on the brightest target in the observing sequence. Saturation occurs at a sum of ~ 300 counts (150 counts per pixel). If the sum of counts is close to 300, then click the "DIFF/SIG" button on the CLASSIC GUI. Saturation occurs when the signal in the DIFF/SIG window flatlines at the end of the scan (maybe we can get a screen shot to show what saturation looks like). If the signal is saturating, then you need to record at a faster (higher) rate.\\ \\  You don't have to worry about saturation in destructive mode.\\ \\  To determine the best camera speed, go to the faintest star in the bracket:\\ 
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   * When clicking SAVE to start recording data, please visually confirm that the SERVO is ON. If the servo is not on, then the position of the fringes might drift across the window.   * When clicking SAVE to start recording data, please visually confirm that the SERVO is ON. If the servo is not on, then the position of the fringes might drift across the window.
   * After the fringe data have been collected, please look at the power spectrum plots to see if there are any problems with noise peaks showing up in the data. If there are noise peaks in the power spectrum then the cause of these peaks should be investigated (vibrations in the lab? telescope oscillations? electronic noise?).   * After the fringe data have been collected, please look at the power spectrum plots to see if there are any problems with noise peaks showing up in the data. If there are noise peaks in the power spectrum then the cause of these peaks should be investigated (vibrations in the lab? telescope oscillations? electronic noise?).
-\\  This is how the power spectrum for good data should look (at 750 Hz sampling, the fringe power shows up at 150 Hz):\\ {{/file/view/ps_good_2017_12_02_HD26764_005.png/625547393/ps_good_2017_12_02_HD26764_005.png|ps_good_2017_12_02_HD26764_005.png}}\\ \\  This is an example of noise spikes from telescope oscillations contaminating the power spectrum (there is a narrow noise peak showing up at the data frequency of 150 Hz, and several other peaks showing up at different frequencies):\\ {{/file/view/ps_peaks_2017_12_02_HD26764_004.png/625547397/ps_peaks_2017_12_02_HD26764_004.png|ps_peaks_2017_12_02_HD26764_004.png}}+\\  This is how the power spectrum for good data should look (at 750 Hz sampling, the fringe power shows up at 150 Hz):\\  
 +{{chara:files:ps_good_2017_12_02_HD26764_005.png|ps_good_2017_12_02_HD26764_005.png}}\\ \\  This is an example of noise spikes from telescope oscillations contaminating the power spectrum (there is a narrow noise peak showing up at the data frequency of 150 Hz, and several other peaks showing up at different frequencies):\\ {{chara:files:ps_peaks_2017_12_02_HD26764_004.png|ps_peaks_2017_12_02_HD26764_004.png}}
chara/classic_guidelines.1517273426.txt.gz · Last modified: 2018/01/29 19:50 by 127.0.0.1

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