Following the successful use of ASTAP in the previous session (S870, 2021-03-14) to identify where the telescope was pointing, a new button routine bas been built in AstroMain 3.38.5 to streamline the process of checking and resetting telescope pointing.   The process comprises a series of step with user confirmation at the commencement of each step and where necessary instructions for manual operation by the user where the step can't be achieved by the routine itself.

The new routine is accessed via a button 'Check/Reset Scope Pointing' located on the Main Scope / Sync&Align tab

The routine carries out the following steps :

1. Take 15s (3x3 binned ) locate frame with ST-10 camera on the LX200 main scope using CCDSoft
      record the filepath to image and the current percieved pointing position (OBJCTRA /  OBJCTDEC)
      check the number of stars in the image is sufficient (a minimum of 10 stars is required)
2. Execute ASTAP via Shell/Command Line to plate solve the image   (results written to .INI file)
   CMDLINE="C:\Program Files\astap\astap.exe" -f "C:\Data\CCD Imaging\New\2021-03-16 S00871\_FOCUS\Snap.2021.43.PointingCheck.FIT" -r 5 -wcs
   
3. Review Plate Solution
    read .INI file and extract  Ra, Dec, Plate Scale, Rotation Angle (including necessary transforms & conversions)
    calculate the offset between the current perceived pointing position and the measured pointing position
4. Reopen image file in CCDSoft and update OBJCTRA/OBJCTDEC with the measured pointing position.
5. Image Link in TheSky6
6.  Invite user to review the plate solution in TheSky6 and if acceptable ask them to perform series of manuals tasks to Sync Telescope to the measured pointing position in away that prepares TPoint for a Short Mapping Run.
7. Commence Short Mapping Run
8. Finish

The new button routine was used in session S871 (2021-03-16).  

• An initial problem was encountered whereby the locate frame was only 100x100 pixels in size and only contained 4 stars causing the routine to exit as per its design.
  Problem was due to sub-framing still being active following a prior autofocusing run. 
  Problem was worked around in-session by manually cancelling the subframing in CCDSoft and then re-running the new button routine.
  Problem needs to be fixed by adding extra code to routine.
     Action:  Clear sub-frame and set camera to full-frame mode before taking locate frame in Step 1
   
• Upon rerunning the new button routine, the process worked well (extract from report file is shown below)
     Action:  Correct minor formatting/reporting issues
   
  
• The Short Mapping Run successfully mapped 7 out of the 8 points specified.  Whilst TPoint only requires 6 points,  I prefer to have at least 9 points
  mapped and therefor manually initiated a second Short Mapping Run to achieve this number.
    Action:  Setup Short Mapping Runs to attempt 12 points by default.  Adding 4 points to the existing 8 spot pattern
                   ( at N,E,S,W positions) to achieve a 12 spot pattern

Extract from report file recording the new routine's action is shown below.

Check/Reset Telescope Pointing          2021-03-16 20:21  (Local)

  Locate Image                          2021-03-16 20:21  (Local)
  Taking 15s image (C)...     Ok        [0000] 20:21:43 (UT)  Full Locate C
    Initial RA:               Ok        07 49 01.199
    Initial Dec:              Ok        +04 19 51.47
    Star Count:               Ok        36 stars

  Plate Solving (ASTAP)                 2021-03-16 20:22  (Local)
  Plate Solution              Ok        Image Successfully Plate Solved in 1.0s
    RA:                       Ok        07 48 57.507
    Dec:                      Ok        +04 16 50.81
    Offset:                   Ok        3.15 min
    ImageScale:               Ok        1.399 arcsec/px
    Rotation:                 Ok        179.25 deg

  Check Location                        2021-03-16 20:22  (Local)
  Reopening Fits Image        Ok        
  Update FITS Header          Ok        Setting OBJCTRA/OBJTDEC based On ASTAP's Plate Solution

  Link Image (TheSky6)                  2021-03-16 20:22  (Local)
  Linking image (UCA/USNO*)...Ok        Stars 36, Scale 1.399, Angle 179.26°

Map Local Points                        2021-03-16 20:22  (Local)
  Checking CCD Temp...        Warning   Cooling Capacity [100%] is > 90% (Temp -20.0 °C)
  Checking Focuser ...        Ok        Tube Temp: 5.8 °C
  Getting telescope position  Ok        Az=181.0,  Alt=36.8
  Setting Point Offsets ...   Ok        2.00 degs
  Creating map list...        Ok        local.txt

Auto-Mapping Run                        2021-03-16 20:22  (Local)
  Reading map list ...        Info      local.txt
    Point 1            , 179.04, 34.76
    Point 2            , 179.04, 36.76
    Point 3            , 179.04, 38.76
    Point 4            , 181.04, 34.76
    Point 5            , 181.04, 38.76
    Point 6            , 183.04, 34.76
    Point 7            , 183.04, 36.76
    Point 8            , 183.04, 38.76
  Reading map list            Ok        (8 points)

  Commencing Auto-Mapping Run

1/8 - Preparing to map Point 1         Point 1

    (details for point 1/8 to 7/8 not shown here)

8/8 - Preparing to map Point 8         Point 8

  Checking Target                       2021-03-16 20:27  (Local)
    Declination :                       6.2 deg
    Altitude :                          38.76 deg (Az: 183.0 )
    Galactic Plane Offset :             15.3 deg
    Proposed exposure :                 10s (Zone: 2-2)

  Slewing                               2021-03-16 20:27  (Local)
  Turn Off Tracking..         Ok        Telescope Tracking is OFF
  Slewing (Az/Alt)...
  Slewing (Az/Alt)...         Ok        
  Slewing Time:               Info      10s (overall)
  Scope Speed:                Info      7.8 deg/s         (66.0 degs in 8s)
  Dome Speed:                 Info      NaN deg/s         (0.0 degs in 0s)
  Checking Dome Position ...  Ok        Dome Azimuth:     182.9 degs
  Checking Dome Position ...  Ok
  Turn On Tracking..          Ok        Telescope Tracking is ON

  Locate Frame                          2021-03-16 20:28  (Local)
  Taking 10s image (C)...     Ok        [00871008] 20:28:15 (UT)  Full Automap C

  Mapping Point                         2021-03-16 20:28  (Local)
  Telescope disconnected
    Image/Object              RAW       Map Point 8
    Exposure                  10s       [00871008] 3x3 10s C -20.4°C
  Inventory Num:              Ok        nInventory = 33
  Linking image (UCA/USNO)... Ok        Stars 31, Scale 1.399, Angle 179.2°
  Checking WCS...             Ok        WCS center matches that from image link 
  Linking Time:               Info      1.8s
    Pointing Error            ?         arc mins
    Scope Discrepancy         0.0       arc mins
    Camera Position Angle     179.2     deg
    Analysing stars ...       Ok        Stars= 31/31
    Normalised ZP             21.01     
    Altitude                  39.0      deg (Airmass 1.590)
    Sky Brightness            11.78     ADU/sq.arc sec/sec, bkgd: 428 ADU, dark: 197.5 ADU(C)
    FWHM                      3.5       arc sec (bright: 6.4, next4: 3.5)
  Link Check                  Ok        Successful Link (31 stars, UCAC2/USNO)
  Telescope re-connected
  Mapping point ...           Ok        Point 8 successfully mapped
  Mapping Success:            7 / 8     (87.5%)

Completed Auto-Mapping Run
  Mapped 7 out of 8 points

  Return to Original Position           2021-03-16 20:28  (Local)
  Checking Altitude ...       Ok        Altitude          36.7 degs
  Checking Azimuth ...        Ok        Azimuth           179.7 degs
  Slewing ...                 Ok        Starting Position
  Checking Dome Position ...  Ok
  Apparent Dome Speed...      Info      7.8deg/min (3.0 degs, 23s)

Operation...                  Completed

 

As part of an attempt to better understand and improve autoguiding performance issues (see Investigation - Guiding Issues (West of Meridian), 2021-01-16) the SBIG power cable and the ZWO 178MC USB 3 cable were rerouted ahead of the session (S870, 2021-03-14) . Instead of passing from the back of the imaging train to the right hand fork & then indirectly to floor  the cables were rerouted to take them back up to the OTA and then down to the right hand fork & then indirectly to the floor.   Due to poor conditions (Cloud/Wind) there was minimal opportunity for establishing the benefits or otherwise of the new cable routing.

Conditions in S871 (2021-03-16) were slightly better and there was some opportunity for looking at the guiding performance using the new routine.