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--- chara:archived_procedures [2025/06/13 17:33]
gail_stargazer
+++ chara:archived_procedures [2025/06/13 17:46] (current)
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@@ Line 111: / Line 111: @@
 ====   ====
-===== OLD ALIGNMENT SEQUENCES =====
+===== 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 ====
@@ Line 124: / Line 141: @@
   - 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.
+      - **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.
@@ Line 140: / Line 157: @@
       - 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
+  - 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
@@ Line 176: / Line 193: @@
 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 **__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.

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