David's Astronomy Pages
Notes - Session 955 (2022-01-17)

 
Bullet Session Aims & Highlights
 - Observing Result
 - Night Summary Plot
 - Session Event Log
 
Bullet Operational Issues
  - Critical Issues (0),  Major Issues (1),  Minor Issues (1),  Small Defects (3),  Continuous Improvement (8)
 
Bullet Images from 2022-01-17 >>         [ Local Files >> ]
Bullet Review - Optimising Guiding & Focusing Times

Session Aims & Highlights (2022-01-17)

Main aims

  1. Targets.  Acquire images of a selection of variable stars, nearby stars, comets & deep sky targets as allowed by time & conditions.
  2. AstroMain.  Test bug fixes associated with AstroMain 3.48.19

Equipment & Software

Highlights

Notes:

  Summary Plots & Logs

Observing Plan
Image
  
Observing Result
Image
   
  
Dome & Scope Slewing Performance
Image
  
Slew/Centering Performance
Image
  
Guiding Performance
Reasons for poor Dec guiding :
Orange points (12)   - Non effective Dec Guiding (South),  'Dec Jitter' (seen once before at this position) or poor seeing.
Yellow Point (6, 7,14)   - Point 6: a 4" Dec Spike in frame 4 was 'overcorrected' pushing the guidestar to the wrong side of zero line. Point 7: Non-effective Dec Guiding esp. in frame 4.  Point 14: Marginally non-effective guiding (south) and sometimes on wrong side of zero line.
Image 
Image
 
  
Sky Conditions (Locate Frames)
Image
 
Night Sky Summary Plot
Top axis: Sky Brightness at Zenith (in ADU/s)
Lefthand axis: Local Time (hh LT). Righthand axis: Sun Altitude (degs)

Image   
  
Actual Weather vs Pre-Session Weather Forecast
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Image   
  
Session Event Log
Time     Event Detail
17:29:53   Camera1 Connected SBIG Camera Connected (set point -15°C)
17:29:55 Session Created Live Session Created (2022-01-17 S00955, ImageSaveNum: 955001)
17:29:57   Scope Switched On Telescope Power has been switched on via UPB Powerbox.
17:31:37   Services Started Observatory Services started
17:53:11 Observatory (Manual) Observatory placed in Manual Mode
17:53:28 Observatory (Auto) Observatory placed in Fully-Automated Mode
17:53:31 Session Pending Session pending (2022-01-17)
17:53:33 Session Initiating Session initiating (2022-01-17)
17:53:35   Plan Requested Observing Plan requested from AstroPlan (1.29.2)
17:53:54   Plan Loaded Observing Plan loaded to queue (, Plan ID: 710)
17:54:07   Camera1 Connected SBIG Camera Connected (set point -25°C)
17:55:43   Telescope Connected Telescope Connected (TheSky6)
17:55:45 Observatory (Manual) Observatory placed in Manual Mode
17:57:23   Services Stopped Observatory Services stopped
17:57:30 Program Closed Program closed by User
19:30:19 Session Monitoring AutoStart monitoring for Live Session opportunity between 19:30 & 06:18
19:30:22 Session AutoStarting Session autostarting (19:30)
19:30:50 Session Resumed Live Session Resumed (2022-01-17 S00955, ImageSaveNum: 955001)
19:31:09   Services Started Observatory Services started
19:31:14 Observatory (Auto) Observatory placed in Fully-Automated Mode
19:31:17 Session Pending Session pending (2022-01-17)
19:31:20 Session Initiating Session initiating (2022-01-17)
19:31:28   Plan Loaded Observing Plan loaded to queue (, Plan ID: 710)
19:31:52   Camera1 Connected SBIG Camera Connected (set point -25°C)
19:31:59   Telescope Connected Telescope Connected (TheSky6)
19:32:23 Session Equilibration Session ready for dome & camera equilibration
19:33:08   Dome Opened Dome opened (opening time 45s)
19:33:11 Session Running Session running
19:33:13   Queue Started Observing Queue started (42 targets selected)
19:33:16     Target Started (NrZen) Target started (Focus Field 3, HIP 14181)
19:34:57       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
19:38:10       Focusing Completed Foc1 AutoFocus Completed (Profile No 1, wide)
19:39:55       Focusing Failed Foc1 focusing failed (failed QC check - Ambiguous)
19:39:57       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap)
19:42:07       Focusing Completed Foc2 AutoFocus Completed (Profile No 2, wide)
19:43:54       Focusing Completed Foc2 AutoFocus Completed (Profile No 2)
19:44:11     Target Completed Target completed (Focus Field 3, HIP 14181)
19:44:16     Target Started (7/48) Target started (7/48, NGC 958 w/SN2022ao)
19:47:39       Focusing Skipped Foc1 focusing skipped - star is lost (TCF-S)
19:54:31     Target Completed Target partially completed (7/48, NGC 958 w/SN2022ao)
19:54:35     Target Started (8/48) Target started (8/48, Nova Per 2020)
19:57:38       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
20:00:51       Focusing Completed Foc1 AutoFocus Completed (Profile No 3, wide)
20:02:49       Focusing Completed Foc1 AutoFocus Completed (Profile No 3)
20:09:48     Target Completed Target partially completed (8/48, Nova Per 2020)
20:09:52     Target Started (9/48) Target started (9/48, GCVS CN Ori)
20:13:15       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
20:15:39       Focusing Completed Foc1 AutoFocus Completed (Profile No 4)
20:23:14     Target Completed Target partially completed (9/48, GCVS CN Ori)
20:23:18     Target Started (10/48) Target started (10/48, GCVS GK Per)
20:26:05       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
20:28:26       Focusing Completed Foc1 AutoFocus Completed (Profile No 5)
20:32:25     Target Completed Target completed (10/48, GCVS GK Per)
20:32:29     Target Started (11/48) Target started (11/48, GCVS U And)
20:35:29       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
20:37:42       Focusing Completed Foc1 AutoFocus Completed (Profile No 6)
20:46:55     Target Completed Target partially completed (11/48, GCVS U And)
20:46:59     Target Started (12/48) Target started (12/48, NGC 7594 w/SN2022de)
20:49:59       Focusing Skipped Foc1 focusing skipped - star is too dim (TCF-S)
21:06:23     Target Completed Target completed (12/48, NGC 7594 w/SN2022de)
21:06:27     Target Started (13/48) Target started (13/48, C/2019 L3 (ATLAS))
21:09:50       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
21:12:10       Focusing Completed Foc1 AutoFocus Completed (Profile No 7)
21:21:51     Target Completed Target completed (13/48, C/2019 L3 (ATLAS))
21:21:55     Target Started (14/48) Target started (14/48, GCVS FU Ori)
21:24:35       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
21:27:02       Focusing Completed Foc1 AutoFocus Completed (Profile No 8)
21:30:39     Target Completed Target completed (14/48, GCVS FU Ori)
21:30:43     Target Started (15/48) Target started (15/48, GCVS RR Tau)
21:33:29       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
21:35:40       Focusing Completed Foc1 AutoFocus Completed (Profile No 9)
21:42:34     Target Completed Target partially completed (15/48, GCVS RR Tau)
21:42:38     Target Started (16/48) Target started (16/48, GCVS BL Lac)
21:46:22       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
21:48:48       Focusing Completed Foc1 AutoFocus Completed (Profile No 10)
21:52:53     Target Completed Target completed (16/48, GCVS BL Lac)
21:52:57     Target Started (17/48) Target started (17/48, Nova Cas 2021)
21:56:01       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
21:57:47       Focusing Completed Foc1 AutoFocus Completed (Profile No 11)
22:04:41     Target Completed Target completed (17/48, Nova Cas 2021)
22:04:45     Target Started (18/48) Target started (18/48, AT2021rl)
22:09:29       Focusing Skipped Foc1 focusing skipped - star is lost (TCF-S)
22:26:20     Target Completed Target completed (18/48, AT2021rl)
22:26:25     Target Started (19/48) Target started (19/48, 67P/Churyumov-Gerasimenko)
22:30:10       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
22:32:45       Focusing Completed Foc1 AutoFocus Completed (Profile No 12)
22:46:02     Target Completed Target completed (19/48, 67P/Churyumov-Gerasimenko)
22:46:06     Target Started (20/48) Target started (20/48, Scholz's Star)
22:49:20       Focusing Skipped Foc1 focusing skipped - star is too dim (TCF-S)
23:05:53     Target Completed Target completed (20/48, Scholz's Star)
23:05:57     Target Started (21/48) Target started (21/48, GCVS SY Cnc)
23:08:45       Focusing Skipped Foc1 focusing skipped - star is lost (TCF-S)
23:12:10     Target Completed Target completed (21/48, GCVS SY Cnc)
23:13:10     Target Started (22/48) Target started (22/48, GCVS SU Tau)
23:16:01       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
23:18:26       Focusing Completed Foc1 AutoFocus Completed (Profile No 13)
23:24:01     Target Completed Target completed (22/48, GCVS SU Tau)
23:24:05     Target Started (23/48) Target started (23/48, GCVS NV Ori)
23:27:05       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
23:29:17       Focusing Completed Foc1 AutoFocus Completed (Profile No 14)
23:34:16     Target Completed Target completed (23/48, GCVS NV Ori)
23:34:20     Target Started (24/48) Target started (24/48, AT2021agoa (CV))
23:37:19       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
23:39:18       Focusing Completed Foc1 AutoFocus Completed (Profile No 15)
23:45:24     Target Completed Target completed (24/48, AT2021agoa (CV))
23:45:28     Target Started (25/48) Target started (25/48, SN 2021aalq)
23:49:26       Focusing Skipped Foc1 focusing skipped - unable to find a star (TCF-S)
00:02:26   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars)
00:05:30     Target Completed Target completed (25/48, SN 2021aalq)
00:05:32   Queue Paused Queue paused for Session Suspension
00:05:34 Session Suspended Session suspended
00:06:22   Dome Closed Dome closed (closing time 50s)
00:15:38     Target Cancelled Target cancelled (26/48, GCVS RZ LMi) due to cloud
00:36:00     Target Cancelled Target cancelled (27/48, NGC 4227 w/SN2021biz) due to cloud
00:57:52     Target Cancelled Target cancelled (28/48, UGC 4671 w/SN2021afsj) due to cloud
01:10:10     Target Cancelled Target cancelled (29/48, GCVS ER UMa) due to cloud
01:30:02     Target Cancelled Target cancelled (30/48, NGC 3389 w/AT2021hkw) due to cloud
01:51:54     Target Cancelled Target cancelled (31/48, AT2021djx) due to cloud
02:13:46     Target Cancelled Target cancelled (32/48, NGC 4896 w/SN2021wad) due to cloud
02:35:39     Target Cancelled Target cancelled (33/48, IC 4040 w/SN2022jo) due to cloud
02:57:30     Target Cancelled Target cancelled (34/48, UGC 8426 w/AT2021knq) due to cloud
03:10:57     Target Cancelled Target cancelled (35/48, GCVS RR Leo) due to cloud
03:30:33     Target Cancelled Target cancelled (36/48, NGC 3836 w/SN2021aefs) due to cloud
03:52:25     Target Cancelled Target cancelled (37/48, UGCA 258 w/SN2022mm) due to cloud
04:06:17     Target Cancelled Target cancelled (38/48, AT2021aena (CV)) due to cloud
04:26:09     Target Cancelled Target cancelled (39/48, M61 w/AT2021ilb) due to cloud
04:48:01     Target Cancelled Target cancelled (40/48, NGC 4348 w/SN2022fw) due to cloud
05:09:54     Target Cancelled Target cancelled (41/48, UGC 5528 w/SN2022B) due to cloud
05:31:45     Target Cancelled Target cancelled (42/48, NGC 4165 w/SN2021gno) due to cloud
05:53:37     Target Cancelled Target cancelled (43/48, NGC 6184 w/SN2021wkv) due to cloud
06:10:07     Target Cancelled Target cancelled (44/48, C/2017 K2 (PANSTARRS)) due to cloud
06:21:44     Target Cancelled Target cancelled (45/48, AT2021agpw (CV)) due to cloud
06:33:24     Target Cancelled Target cancelled (46/48, GCVS U Her) due to cloud
06:42:45     Target Cancelled Target cancelled (47/48, GCVS SS Her) due to cloud
07:01:31     Target Cancelled Target cancelled (48/48, GCVS R CrB) due to other condition
07:01:36   Queue Completed Job Queue completed
07:01:38 Session Closing Session closing
07:01:43   Dome Closed Dome already closed (closed at 00:06, closing time 50s)
07:02:06   Dome Parked Dome parked (parking time 15s), Az: 90.0 deg
07:03:12   Telescope Parked Telescope parked (parking time 62s)
07:03:27   Telescope State Scope parked Turn scope off. (Handbox)
07:03:49   Telescope Switched Off Telescope Power has been switched off via UPB Switch.
07:04:45   Services Stopped Night Services stopped
07:04:47 Session Housekeeping Housekeeping Started (Cleanup FITS, Create Fits Summary, Transfer Files)
07:05:03 Session Finished Session Finished
 
Session Alerts
Time     Alert Detail
17:55:45 Scope Alert TheSky's scope is reporting a RA=0/Dec=0 position or is not connected
17:55:52 Scope Alert TheSky6's scope is reporting a RA=0/Dec=0 position

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Operational Issues (2022-01-17, S955)

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Critical Issues

Major Issues

Minor Issues

Small Defects

Continuous Improvement

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Review - Optimising Guiding & Focusing Times

Issue: For some Guide Runs the time gap between the final focusing movement and the start of the first image frame is still unneccessarily long.  For some guide runs (eg Guide Run 8, 16, ) there is still a gap of around 30s.  

Review:  Reviewing timings for CN Ori (Target 9/48,  Guide Run 3, Focus Profile 4)

20:11:38 ScopeMode.Guiding
20:11:39 Start Guide
20:11:40 Set Dec Guide Mode / PreJog
20:11:57 Finish/Save Cam2 Reference Frame (10s)
20:12:22 Finish Linking Cam2 Reference Frame (9.2s + 9.5s + 0.9s)
20:12:23 ConvertFitsToJpg (Cam2 Ref)
20:12:25 Send GuideRequest (timeout 15s)
20:12:54 Start PHD2Guiding Monitor (28s)
20:12:54 ConvertFitsToJpg (FocusFrame GuideRef)
20:12:55 Sleeping for 3.1s to throttle BatchFile executions.
20:12:54 ConvertFitsToJpg (FocusFrame  Guide03_F1)
20:13:00 Start FocusMainScope (Foc1)
20:13:02 Take Focus Locate Frame (3s)
20:13:10 Take Focus Frame (3s)
20:13:15 Start Focus Profile
20:13:25 Finish Focus Move to Start of Focus Range (10s)
20:15:14 Finish Profile Steps 
20:15:23 Finish Focus Move to Best Focus Position (9s)
20:15:23 Take 3 focus frames at best focus (11s)
20:15:39 Finish 12s delay    (delay after making a large (>250 steps) focus change .   This delay was 20s at one stage)
20:15:51 Set ScopeMode Imaging.
20:15:58 Begin TakeMainScopeFrame
20:16:06 Finish Focus Move to Best Focus, V Filter (8s)
20:16:16 Finish 10s delay  (delay after making a large (>250 steps) focus change)
20:16:16 Adjust Lock Position
20:16:16 Starting 20s delay after resetting lock position (ReleaseFromWaitTime = Now().AddSeconds(20) )
20:16:32 Adjust Lock Position
20:16:43 Check Focus Position (0s,  but could be 4-10s)
20:16:43 Take First Frame

Example Charts

Begin Guiding Chart for CN Ori (Guide Run 3)

Image

Operations (mins) CN Ori  U And  RR Tau 
Planned Duration  12.70  14.10  11.10
Waiting  0.00  0.00  0.00 
Slewing  0.56 0.50  0.40 
Centering  0.95  1.01  0.80 
Focusing  2.65  2.50  2.53 
Imaging  7.32  8.95  6.64 
SubTotal  11.48  12.96  10.37 
unallocated  1.96 ?  1.55 ?  1.55 ? 
Total  13.44  14.51  11.92 

Conclusion
Several opportunities to reduce time.

1) 10-25s of time could be saved by carrying out Cam2 Reference Frame Locate and Start Guiding operations in parallel.
 - the issue blocking this is the management of the two Report Messages streams which are designed to be serial tasks at present.
-  prehaps the Start Guiding messages could be temporaily 'saved' and then reported in one go at the end of Locate Cam2 Frame operations.

2) Time can be saved by eliminating 3 frame focus check at end of a focus profile>

3) Can the 12s delays be reduced or eliminated ?

Actions
 

Image Check Focus (3 frames). Remove 3 frame Focus Check at end of Profile in cases where Focus Mode is auto And target isn't a Near Zenith Focus Field And target isn't well ahead of schedule.   How to determine whether there is sufficient time for the Check Focus or not ?
Focus Profile is performed if Session.DeltaMinsFromPlan < -3.5

Image Deferred Focus. Reinstate deferral of the end of profile move to best focus when first filter is not C and Check Focus isn't being performed.

Image Delay after Focus change. Reduce delay after large focus change from 12s to a standard 10s.

Image Parallel Activity. Consider possibility of making Locate Cam2 Reference and Request Guiding a parallal activity. 
On Hold

Update 2022-01-21
Session S956 (2021-01-20) was run using new default timings:  Slew(80s, unchanged),  Locate&Centre (120s),  BeginGuiding (90s), Focusing (150s), BeginImaging (60s).

Wait time at the start of many targets was frequently around 2 minutes, but sometimes up to 4 minutes.  Total wait time may have been as high as 43mins equivalent to 2 or 3 whole targets.  These waits are partly due to 1) overall impact of changes to default times (the explicit inclusion of 150s for focusing and 60s to Begin Imaging, and extra extra time to Begin Guiding with reduction in time allowed for centering ) and 2) some targets ending 2 mins earlier than planned in cases where focusing is cancelled early due to focus star being determined as 'too dim' or 'lost'. 

The average task times over the S956 session were :  slewing 33s (vs 80s plan),  centering 77s  (vs 120s plan), begin guiding 56s (vs 90s plan),  aborted focusing 30s (vs 150s plan), completed focusing 163s (vs 150s plan), begin imaging 19s (vs 60s plan).  

Looking at longest task instances : longest slew was 81s (vs 80s plan), longest centering was 180s (vs 120s plan),  longest begin guiding 65s (vs. 90s plan), longest focusing 184s (vs 150s plan),  longest begin imaging 54s (vs 60s plan).  

On the other hand U And had an actual duration of 15.5 mins (excl. waiting) vs a scheduled duration of only 12.6 mins. The overrun is due to the frequent focus changes associated with each filter change ( 3 x BVRI, so a total of 12 filter/focus changes).   When focus change is large one (including taking out focuser backlash) an extra 10s is added to allow guiding to resettle & be checked.   Current timings assume only 2s per filter change.

The order that filters are changed affects the timings significantly   Decreasing filter step position ( 2 large focus change + 10s settle) takes 17s but increasing focus step position (a single small focus change) takes just 3s.  A BVRI set carries an overhead of 54s (3 x 17s + 1 x 3s), but optimising the filter order would carry an overhead of only 26s (3 x 3s + 1 * 17s) a saving of 28s (or 84s for a 3 x BVRI sequence).       A fully optimised sequence (say III-RRR-VVV-BBB) might carry an overhead of only 9s vs a 162s overhead for BVRI-BVRI-BVRI sequence.  

For the timing being filter operations/order will be left unchanged as most targets involved only C Filter imaging, however extra time clearly need to be incorporated for making the filter changes that are currently programmed.

Proposal new timing allowances for planning (2022-01-21 onwards) are :

Task New Time (s)  Previous Time (s)
Slewing   70s 80s
Centering   100s 120s
BeginGuiding   60s 90s
Focusing   150s unchanged
BeginImaging   30s 60s
Filter Change 10s 2s

Caveats : Things are not allowed for in calculated expected target durations are:

- impact of dome slewing slippages/holdups that may delay target slewing
  (plan assumes 70s average time of slewing)

- impact of cloud that will number of centering attempts and centering exposures that may delay target centering
  (plan assumes a 100s average time for centering)

- guiding issues that may require extra adjustments between frames 
   (plus assumes 'perfect' guiding with no extra delays between frames)

- carry over of wide search focusing on to 1st/2nd targets if focusing is not achieved for near zenith focus field
    (plan assumes 150s average time for focusing which is the time for a single focus profile only)

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