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--- chara:new_alignment_procedures [2023/08/09 09:24]
charaobs
+++ chara:new_alignment_procedures [2023/09/22 20:02] (current)
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@@ Line 1: / Line 1: @@
 ====== New Alignment Sequences ======
-At the start of the night, align the red and blue beacons following the "Beacon Alignments" section in the [[:chara:operating_procedures|Operating Procedures]]. These alignments should be done with the telescope at stow with M7 in the default position. During this process, use the Dichroic to align the blue beacon to the labAO WFS. Because we are no longer sending M7 to the default position during the slew sequence, this is the only time that we should adjust the dichroic.
+**THIS PAGE IS NO LONGER MAINTAINED** - See relevant sections in the [[:chara:new_operating_procedures|New Operating Procedures]].
+At the start of the night, align the red and blue beacons following the "Beacon Alignments" section in the [[:chara:new_operating_procedures|Operating Procedures]]. These alignments should be done with the telescope at stow with M7 in the default position. During this process, use the Dichroic to align the blue beacon to the labAO WFS. Because we are no longer sending M7 to the default position during the slew sequence, this is the only time that we should adjust the dichroic.
 **IMPORTANT NOTE:** For the beacon/dichroic alignment at the beginning of the night, the red beacon must be aligned to the default starlight boxes. You can either zero out any offsets between the beacon (green) boxes and the starlight boxes on the telescope WFS (using ZERO BCN) or use the starlight (blue) boxes to align the red beacon during this step.
@@ Line 98: / Line 100: @@
   - **If the coma and astigmatism terms are high on the aberration plots create a new sky flat using the SV FLT button on the obsgtk. Turn off the DM servo, flatten, then relock the DM servo. The DM servo uses the flat to guide the optimal correction. If the signal is good on the tel WFS, it is a good idea to make a new sky flat on every star. **
   - With the star locked on telescope WFS and blue beacon locked on labAO, move the beacon flat to align the starlight into the STST reference boxes. The green cross marks the center of the box and is your target, the red cross marks the centroid of star. If the star is within the STST reference box, then click the "STST" button on the obsgtk main tab to automatically align the beacon to move starlight to the center of the reference box (use step size close to 200). This may be very slow or not work at all.
-  - If the star is outside of the STST reference box, move the beacon manually. Refer to the rotation matrix wheel printout on the desktop to know which way to move. The first few clicks may not move at all due to hysteresis in the actuators. Do this process slowly, as M7 will slowly move to compensate for the beacon shift and keep the blue beacon aligned to labao. If the blue beacon did not move when clicking the beacon flat, click again as it was taking up slack in the movement. the labao DMTilt can handle up to 3 units of tilt to offload to the M7.  If the values reported on the obsgtk (labao X,Y, tilt, Focus line) are lower than this, you can click again.
+  - If the star is outside of the STST reference box, move the beacon manually. Refer to the rotation matrix wheel printout on the desktop to know which way to move. The first few clicks may not move at all due to hysteresis in the actuators. Do this process slowly, as M7 will slowly move to compensate for the beacon shift and keep the blue beacon aligned to labao. If the blue beacon did not move when clicking the beacon flat, click again as it was taking up slack in the movement. the labao DMTilt can handle up to 3 units of tilt to offload to the M7. If the values reported on the obsgtk (labao X,Y, tilt, Focus line) are lower than this, you can click again.
   - If the required move is large, ~1000 steps on the beacon flat, or about 25 pixels on STST, it may help to turn the Labao Servo and DM AUTO off and manually move the blue beacon with M7 back to center on labao until the flux is closer to the STS center. AUTO M7 can also be used for medium sized moves, ~333-500 steps or so of the beacon flat.
   - When the star is aligned on STST, tun off the DM servo and TT, move the star away, and turn on the Red Beacon.
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 Faint stars (H > 5 mag) will not be easily visible in STST. Slew to a nearby bright star to align the beacon flat and set the beacon box offsets on the TWFS. Then slew to faint star and skip steps 9-15 above. NOTE: The STST centroiding now works for longer exposure times. See note in STST section above about how to change exposure time and coadds.
-Programs with bright IR stars may not need any red beacon alignments when slewing and can just use the M7 and labao focus alignments.  Lock the star on the blue boxes and use the STST to fine tune any misalignment of the beacon flat.
+Programs with bright IR stars may not need any red beacon alignments when slewing and can just use the M7 and labao focus alignments. Lock the star on the blue boxes and use the STST to fine tune any misalignment of the beacon flat.
 ==== Changing Beam Configuration During the Night ====

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