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chara:operating_procedures [2023/08/05 19:49]
charaobs 		chara:operating_procedures [2023/08/18 20:56]
gail_stargazer
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 **NOTE:**  There are now two sets of boxes on the TWFS. The blue boxes are for locking on starlight and are the default reference position. The green boxes can be offset from these to correct for the misalignment between the beacon and the IR starlight. At the beginning of the night, the red beacon must be aligned to the blue starlight boxes with the telescope at stow (see [[:chara:new_alignment_procedures|New Alignment Procedures]]). You can zero out any offsets between the green beacon boxes and the blue starlight boxes on the telescope WFS using [ZERO] or [ZERO BCN]. **NOTE:**  There are now two sets of boxes on the TWFS. The blue boxes are for locking on starlight and are the default reference position. The green boxes can be offset from these to correct for the misalignment between the beacon and the IR starlight. At the beginning of the night, the red beacon must be aligned to the blue starlight boxes with the telescope at stow (see [[:chara:new_alignment_procedures|New Alignment Procedures]]). You can zero out any offsets between the green beacon boxes and the blue starlight boxes on the telescope WFS using [ZERO] or [ZERO BCN].
  
-Turn on the ACQ camera in the obsgtk. Make sure that the beacon is going through the hole in the acquisition display. If not, use Beacon UP/DOWN etc buttons on a HUT gui or WFS tab on the obsgtk to move it into the hole. Look for spots to be in boxes on the WFS display. Turn on the boxes on the obsgtk [BOXES] to see how the alignment is. The boxes may be in the default position or may be moved to a position that worked better when observing. Load the default boxes with the [DEFBX] button, then move them to center on the beacon when it is centered in the ACQ hole.  This ensures a more even illumination of spots in the boxes. As the red beacon is bright, use low gains, ie. 30-50 for the BARE dichroic, 70-100 for VIS or 200/300 for the IR dichroic, to make these alignments. If the red beacon spots on the WFS display are in the boxes, press [ALIGN BEACON] on the ALIGN tab on the TWFS GUI or [ALN BCN] on the obsgtk, wait for completion. The values should reach zero in both the X and Y axes. The default maximum number of tries is 10 so if it is not aligned before it ends, repeat the step if needed.+Turn on the ACQ camera in the obsgtk. Make sure that the beacon is going through the hole in the acquisition display. If not, use Beacon UP/DOWN etc buttons on a HUT gui or WFS tab on the obsgtk to move it into the hole. Look for spots to be in boxes on the WFS display. Turn on the boxes on the obsgtk [BOXES] to see how the alignment is. The boxes may be in the default position or may be moved to a position that worked better when observing. Load the default boxes with the [DEFBX] button, then move them to center on the beacon when it is centered in the ACQ hole. This ensures a more even illumination of spots in the boxes. As the red beacon is bright, use low gains, ie. 30-50 for the BARE dichroic, 70-100 for VIS or 200/300 for the IR dichroic, to make these alignments. If the red beacon spots on the WFS display are in the boxes, press [ALIGN BEACON] on the ALIGN tab on the TWFS GUI or [ALN BCN] on the obsgtk, wait for completion. The values should reach zero in both the X and Y axes. The default maximum number of tries is 10 so if it is not aligned before it ends, repeat the step if needed.
  
 Turn labao camera [ON] and [START] the display. Make a dark with the [MKDRK] button in the LABAO section of the obsgtk. Turn on the blue beacon. The blue beacon should show spots on the LABAO display. Adjust the FPS lower if they are dim. 100 FPS is the default, but 40 is often used for observing. **Set the M7 mirror to the default position.**  Then use the blue DICHROIC buttons on the WFS tab of the obsgtk or HUT gtk to get them in the boxes. When the spots are inside the boxes, press [SCOPE DICH] in the ALIGN tab on the LABAO GUI or the [ALN DICH] on the MAIN tab of the obsgtk to align the spots. Turn labao camera [ON] and [START] the display. Make a dark with the [MKDRK] button in the LABAO section of the obsgtk. Turn on the blue beacon. The blue beacon should show spots on the LABAO display. Adjust the FPS lower if they are dim. 100 FPS is the default, but 40 is often used for observing. **Set the M7 mirror to the default position.**  Then use the blue DICHROIC buttons on the WFS tab of the obsgtk or HUT gtk to get them in the boxes. When the spots are inside the boxes, press [SCOPE DICH] in the ALIGN tab on the LABAO GUI or the [ALN DICH] on the MAIN tab of the obsgtk to align the spots.
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 Cold temperatures around freezing also can be problematic. Several components are not rated to operate at freezing temps. Do not open unless it is above freezing and keep an eye on the temps if they are still dropping. Otherwise, you are free to observe (assuming the humidity, dust, and wind conditions allow it). Here are limits for observing close to 0ºC. Cold temperatures around freezing also can be problematic. Several components are not rated to operate at freezing temps. Do not open unless it is above freezing and keep an eye on the temps if they are still dropping. Otherwise, you are free to observe (assuming the humidity, dust, and wind conditions allow it). Here are limits for observing close to 0ºC.
  
-Temp_warning: T_tel <= 2C or T_outside <= -3C+Temp_warning: T_tel < 2C or T_outside < -3C
  
-Hard_limit: T_tel <= 0C or T_outside <= -5C+Hard_limit: T_tel < 0C or T_outside < -5C
  
 4.6 Essential Observing Links 4.6 Essential Observing Links
chara/operating_procedures.txt · Last modified: 2023/09/01 02:50 by gail_stargazer

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