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--- chara:archived_procedures [2022/01/21 19:40]
charaobs
+++ chara:archived_procedures [2025/06/13 17:46] (current)
gail_stargazer
@@ Line 108: / Line 108: @@
 cosmic_fluor -F -o2 (for a secondary program using secondary ople)
+====   ====
+===== HISTORICAL NOTES ON ALIGNMENT SEQUENCES =====
+==== Beacon Alignments at Stow ====
+**IMPORTANT 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 save the beacon positions after the STST alignment.
+At the beginning of the night, the **red beacon**  must be **aligned to the blue**  starlight boxes with the telescope **at stow**. You can zero out any offsets between the green beacon boxes and the blue starlight boxes on the telescope WFS using [ZERO] on obsgtk or [ZERO BCN] on wfsgtk.
+==== Aberration Terms ====
+==== Check higher order terms - look at abberation plots or at terms displayed on the telaogtk ====
+  - If the astigmatism and coma terms reported by the telescope WFS are high
+      - obsgtk, main tab, [ZCEN] to update the relative box positions for the red beacon obsgtk to zero out higher order terms
+        - or [ZERO_CENT] button on telescope wfsgtk -E for engineering version.
+      - Only perform the ZERO CENT function when the X,Y and focus terms have been brought to near zero.
+==== Alignment Sequence for Visible Combiners: SPICA and PAVO ====
+For the visible combiners the red beacon and starlight will be coaligned, so you only need to use the blue starlight boxes on the telescope WFS.
+<del>**Obsgtk, **main tab, **[ZERO BCN]**  at the start of the night to clear any offset between the position of the beacon boxes and the starlight boxes to avoid any confustion</del>
+For **SPICA**, make sure to do “**useldc **on” in ople server if you haven't done so already.
+  - Slew to star.
+  - Main tab, turn on **[M7AUTO] **to hold the blue beacon during the slew and avoid drifting. It will turn off at the end of the slew.
+  - CD, **[Star Acquired],**  and set new ref pos with **[Opt delay]**
+      - **FOR PAVO: **Do **//NOT //**  hit **[Star Acquired] **before aligning for PAVO, only do **[STAR ACQUIRED]**  after alignment is finished.
+  - Obsgtk, use **[BEACON] **preset for beacon alignment.
+  - Make sure **[DMTILT]**  is off.
+  - **[ALN BCN], **Align red beacon to the blue starlight boxes on the telescope WFS using the beacon flat.
+      - Wfs tab, Use beacon buttons if needed on W1 if beacon gets out of the boxes
+      - or hit RIGHT with 500 stepsize to get them back in.
+  - LABAO section, **[ALN M7], **Align blue beacon to lab WFS using M7.
+      - WFS tab, use the yellow M7 buttons to get centered if beacon is not in boxes, then **[ALN M7]**
+      - 150,000 step size moves 1 full row. Directions are normal.
+  - LABAO section, **[FOCUS] **blue beacon on labao WFS if the focus term is high (moves beacon parabola).
+  - TELWFS section, **[FOCUS] **red beacon on TWFS if focus term is high
+  - **[RED OFF] **Turn off red beacon.
+  - Click **[MOVE]**  button then click on star in ACQ window. This will move star into ACQ hole.
+  - Turn off blue beacon and lock star on **[TT].**
+      - Wait a few seconds to let the star fill up the wfs.
+  - Lock star on telescope AO servo (**[****DM]**  button on obsgtk). Both TT and DM servos should be on now.
+  - If needed, move TWFS boxes (use popup from **ADJ**  button on obsgtk) to** get star centered and evenly illuminated on ACQ hole.**  (Note: you might need to close DM AO loop during this step.)- Turn on the blue beacon
+  - Make sure **DMTILT is green**
+      - Stays off during alignments and when locked on star using M7AUTO
+      - Stays on when locked on a star using DMAUTO.
+      - The message from DM tilt “NOT Ignoring DM tilt…” when it is on. (This may take 2 clicks to confirm this message.)
+      - NOTE: The **DMTILT**  button changes whether the x, y numbers at the bottom of obsgtk show box centroids (DMTILT gray) or zernike terms (DMTILT green). The automatic alignment sequences now correctly use the correct x,y calculations regardless of whether DMTILT is green/gray (centroids for aligmments and M7AUTO; zernike terms for DMAUTO).
+  - Turn on **DM AUTO**, **LABAO**.
+  - Align STST for IR
+      - obsgtk, **[STST]**
+      - once centered, turn on guiding
+  - **For PAVO: **make sure carts are in position, then hit **[STAR ACQUIRED**] once alignments are finished. Star acq. starts the camera on pavo.
+  - **For SPICA (no longer do extra spica ipdet alignment)**:
+      - **ip_det_gtk **  (blue chara menu)
+      - **[Start ACQ] **
+      - can adjust display with 200 - 2000 in the max, then hit **[SET]**.
+      - press **[BF/M7 CONTROL] **to open pop up control to align.
+        - use step size of about 32 if on the edge to bring to center. Directions are normal (ex. right is right)
+      - Use **STST **as a reference, if spots are far on ipdet display, stst is probably really off too. Use stst to bring spots close to center and it should help bring spots close to center on ipdet, then use BF/M7 to finish aligning.
+        - use the printed azimuth wheel to get directions of the buttons for SPICA.
+      - let SPICA team know, they may or may not want you to turn on FTT/SERVO.
+      - Once aligned, on STST GUI, press **[CenBox]**  to mark new reference position to monitor any drift.
+      - Make sure data acquired line comes in on CD, otherwise do **[DATA ACQ]. **
+        - or make sure to **[REOPEN]**  CD during shutters
+  - If the coma and astigmatism terms are high on the aberration plots, create a new sky flat
+      - Turn off **[DM]**, **[SV FLT]**, **[FLATEN]**, then relock the **[DM]**
+      - If the signal is good on the tel WFS, it is a good idea to make a new sky flat on every star.
+  - **Check aberration plots.**  If X/Y terms are not going to zero, try stopping servo loops, recentering alignment, and turning back on servo loops. If X/Y and higher order terms still not going to zero after checking alignment and making a new flat, then this likely means a new reconstructor needs to be made.
+  - SPICA uses MIRCX as a fringe tracker and MYSTIC as a fringe finder so having the STST open to monitor the IR beam quality is helpful even if you will not be doing the additional STST beacon flat alignment.
+      - Center the star flux in the Crop boxes with the CenBox button and use the drift from center, along with SPICA team input, to make beacon flat corrections as requested.
+  - At times, Mircx will have such poor flux that a beacon flat correction to align to the STST reference position will be needed. This will occur on **E1 pop 4 ****and 5**  and **S1 pop 5**  due to their extreme distances from the telescope to the lab.
+      - Follow the SPICA team guidance in making this correction to improve the flux to keep Mircx usable as a fringe tracker with those baselines.
+==== Alignment Sequence for IR Combiners: MIRC-X/MYSTIC, CLASSIC/CLIMB, SILMARIL ====
+The path of the IR light will be different from the visible light because of dispersion in the AO dichroic and atmospheric refraction. To compensate for this offset, we have **two sets of boxes**  on the telescope WFS.
+The **__blue boxesu are for starlight** and the **__  green boxesu are for aligning the red beacon**. The offset between these sets of boxes will change depending on the azimuth and elevation of the target.
+The green beacon boxes help keep track of the offset red beacon motion. These are defined as an offset to the starlight position, so if you move the starlight boxes, the beacon boxes will also move. If you move the beacon boxes only they will move.
+Before the start of the night clear any offset between the position of the beacon boxes and the starlight boxes on the telescope WFS using the “ZERO BCN” button on obsgtk.
+Faint stars (H > 5 mag) will not be easily visible in STST. Therefore, before slewing to the first star of the night or when slewing to a different region of the sky, slew to to a nearby bright IR star to align the beacon flat and set the beacon box offset on the TWFS. Then slew to faint star, keeping the red beacon at the same fixed position.
+**NOTE:**  The STST centroiding/servo'ing now works for longer exposure times. If you change exposure time, you need to: stop the camera, config the camera, restart the camera, and retake backgrounds.
+For **H=6 mag**, try changing coadds to 5 or 10 for 1 sec integration.
+For **H=8 mag,**  centroiding has been shown to work using 50 sec exposure (1 coadd).
+*Please update here* if you determine settings that work good for the using the auto STST alignments at different magnitudes.
+**Aligning the scopes before STST:**
+  - On shutters GUI, make sure **[STST]**  is in.
+  - Slew to a star of Hmag 5 or brighter (or adjust exposure time/coadds on STST as needed to see fainter stars).
+      - The Find IRC function on CD can do this quickly.
+      - Enter the target on a empty line, press **[HD]**  once (or appropriate designation), and **[Find IRC] **
+      - will automatically give you a bright star nearby.
+  - Close IR shutters as needed to avoid saturating the combiners.
+  - **[M7AUTO]**  can help keep the blue beacon aligned during the slew.
+  - Obsgtk, use **[BEACON] **preset for beacon alignment.
+  - Make sure **[DMTILT] **is off while aligning. This will display x, y centroids at the bottom of obsgtk.
+  - On the first slew only,
+      - **[ALN BCN], **align red beacon to the __blue star boxes__  on the telescope WFS using the beacon flat.
+  - On subsequent slews,
+      - if the star is bright enough to see in STST (Hmag 5 or brighter), then go to step **12 **
+      - if you can't see the star on STST, then align red beacon__ to the __offset green beacon boxesu (only after green boxes have been set using STST - see below).
+  - **[ALN M7] **Align blue beacon to lab WFS using M7.
+      - If beacon is not in boxes, use the yellow M7 buttons on the WFS tab to get centered
+      - 150,000 step size moves 1 full row. Directions are normal.
+  - Labao section,** [FOCUS]**  blue beacon If focus term is high
+  - TWFS section,** [FOCUS]**  red beacon If focus term is high
+      - (ONLY DO THIS STEP IF RED BEACON IS ALIGNED TO STARLIGHT BOXES - e.g., first slew)
+  - **[RED OFF]**. Make sure you have the blue starlight boxes on telescope WFS.
+  - Click **[MOVE]**  button then click on star in ACQ window. This will move star into ACQ hole.
+  - Turn off blue beacon and lock star on **[TT]**  only.
+  - Lock star on telescope AO servo (**DM**  button on obsgtk). Both TT and DM servos should be on.
+  - If needed, move TWFS boxes (use popup from **ADJ**  button on obsgtk) to** get star centered and evenly illuminated on ACQ hole.**
+      - (Note: you might need to close DM AO loop during this step.)
+  - Turn on the blue beacon.
+  - Turn on DMTilt (will turn green).
+      - stays off during slews
+      - the message from DM tilt will say “NOT Ignoring DM tilt…” when it is on. This may take 2 clicks to confirm this message.
+  - Turn on **DM AUTO**, **LABAO servo**.
+  - If the coma and astigmatism terms are high on the aberration plots, create a new sky flat
+      - Turn off **[DM]**, **[SV FLT]**, **[FLATEN]**, then relock the **[DM]**.
+      - **If the signal is good on the tel WFS, it is a good idea to make a new sky flat on every star.**
+**Aligning STST:**
+  - With the star locked, move the beacon to align the starlight on STST.
+  - On STST GUI, use either Full or Crop view.
+      - 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,
+        - **obsgtk**, main tab, very bottom, click **[STST]**  to automatically move the beacon and M7 simultaneously to align the star to STST. You can do all six at the same time.
+      - If the star is outside of the STST reference box,
+        - Try increasing the size of the STST reference boxes or move the beacon manually using the WFS tab.
+          - Use the azimuth rotation matrix wheel printout on the desk to know which way to move for IR.
+            - point arrow to the objects azimuth.
+            - the direction on the printout corresponds to the direction you want to move on stst.
+            - the direction printed on the wheel is the beacon button to press on obsgtk wfs tab.
+            - So if 'LEFT' is pointed up, press the left button to move stst up.
+          - The first few clicks may not move at all due to hysteresis in the actuators. Do this process slowly, as the labao DM TILT will offload to M7 slowly to compensate for the beacon shift and keep the blue beacon aligned to labao.
+          - If the IR flux 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 tilt values reported on the obsgtk labao tilt are lower than 2 units, you can click again. Steps of 333-500 are typical for the first moves.
+            - 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.
+  - **If this is the first STST alignment star,**  then set the offset position of green beacon boxes on TWFS.
+      - When the star is aligned on STST
+        - turn off the DM servo and TT
+        - move the star away with NEXT
+        - turn on the Red Beacon.
+        - Turn on the boxes
+        - Click “TOGG” on obsgtk (or “TOG BEACON” on WFS gtk) to toggle from the blue starlight boxes to the green beacon boxes on telescope WFS.
+        - Click “SET” button on obsgtk (or “ALIGN BOXES” on WFS gtk) to move the green beacon boxes to the position of the red beacon. This will center the boxes over the beacon and save the new beacon flat positions in a few seconds. Watch the X,Y values of the twfs go to zero. Alternatively, you can use the buttons on the obsgtk ADJ tab pop up window to manually move them.
+        - TOGG back to blue starlight boxes when finished.
+  - **If you will record fringes on this star**
+      - turn off the red beacon
+      - toggle back to the starlight (blue) boxes
+      - MOVE the star to center on ACQ
+      - Turn on **TT**  and **DM**  servo for TWFS.
+      - Turn on **DM AUTO, DMTILT, **and **LABAO**  servo.
+  - **If this is an STST alignment star only**
+      - slew to the first target and align as needed there, which shouldn't be much or at all.
+  - **Check aberration plots. **If X/Y terms are not going to zero, try stopping servo loops, recentering alignment, and turning back on servo loops. If X/Y and higher order terms still not going to zero after checking alignment and making a new flat, then this likely means a new reconstructor needs to be made.
+  - **When slewing to the subsequent stars:**
+      - If you will see the star on STST, then align red beacon using **STST**  auto-alignment button after locking the star.
+      - If you won't see the star on STST, then align the red beacon using the new positions for the green beacon boxes (not the blue starlight boxes), then switch to the starlight boxes when locking starlight. If the slew is close on the sky, you can use the beacon alignment from the previous star. Go back to a nearby bright star if you need to check the beacon alignment on STST (e.g. if flux is lower or fibermaps have degraded on Mircx/Mystic
+      - Always lock the star using the blue star boxes.
+  - When you finish slewing and locking the star on TT, telAO, labAO, then click **[STAR ACQUIRED]**  on Cosmic Debris.
+For programs with bright IR stars, skip align beacon, but do the M7 and labao focus alignments. Then lock the star on the blue boxes and use the STST to fine tune any misalignment of the beacon flat. Check the beacon focus on the twfs occasionally to make sure it stays near zero, every 2-3 stars.

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