David's Astronomy Pages
Notes - Session 926 (2021-10-22)

 
Bullet Session Aims & Highlights
 - Observing Result
 - Night Summary Plot
 - Session Event Log
 
Bullet Operational Issues
  - Critical Issues (0),  Major Issues (3),  Minor Issues (2),  Small Defects (0),  Continuous Improvement (5)
 
Bullet Images from 2021-10-22 >>         [ Local Files >> ]
2021-10-23
Bullet Daytime Tests  - Examination of IR Leakage from Observatory WebCam

Session Aims & Highlights (2021-10-22)

Main aims

  1. Guiding Performance. Make guiding runs to examine the guiding performance after recent installation of new Dec Motor Unit (2021-10-15)
  2.  C/2021 A1 (Leonard). Attempt to first images of comet  C/2021 A1 (Leonard) that is currently passing through Ursa Major which is due to have closest approach in Dec 2021.
  3. Targets.  Acquire images of a selection of variable stars, nearby stars, comets & deep sky targets as allowed by time & conditions.
  4. AstroMain. Check on fixes and new features added to AstroMain 3.44.7

Equipment & Software

Highlights

Notes:

  Summary Plots & Logs

Observing Plan
Image
  
Observing Result
Image
   
  
Dome & Scope Slewing Performance
Image
  
Slew/Centering Performance
Image
  
Guiding Performance
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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Session Event Log
Time     Event Detail
20:58:08 Session Monitoring AutoStart monitoring for Live Session opportunity between 20:58 & 05:54
20:58:11 Session AutoStarting Session autostarting (20:58)
20:58:54   Camera1 Connected SBIG Camera Connected (set point -20°C)
20:58:56 Session Created Live Session Created (2021-10-22 S00926, ImageSaveNum: 926001)
20:58:58   Scope Switched On Telescope Power has been switched on via UPB Powerbox.
21:00:37   Services Started Observatory Services started
21:00:45 Observatory (Auto) Observatory placed in Fully-Automated Mode
21:00:46 Session Pending Session pending (2021-10-22)
21:00:48 Session Initiating Session initiating (2021-10-22)
21:00:50   Plan Requested Observing Plan requested from AstroPlan (1.26)
21:02:53   Plan Loaded Observing Plan loaded to queue (, Plan ID: 676)
21:03:08   Camera1 Connected SBIG Camera Connected (set point -20°C)
21:03:13   Telescope Connected Telescope Connected (TheSky6)
21:03:42 Session Equilibration Session ready for dome & camera equilibration
21:04:27   Dome Opened Dome opened (opening time 45s)
21:04:29 Session Running Session running
21:04:32   Queue Started Observing Queue started (33 targets selected)
21:04:34     Target Started (NrZen) Target started (Focus Field 22, HIP 108888)
21:06:18       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
21:09:10       Focusing Completed Foc1 AutoFocus Completed (Profile No 1, wide)
21:11:31       Focusing Completed Foc1 AutoFocus Completed (Profile No 1)
21:11:34       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap)
21:14:00       Focusing Completed Foc2 AutoFocus Completed (Profile No 2, wide)
21:15:51       Focusing Completed Foc2 AutoFocus Completed (Profile No 2)
21:16:11     Target Completed Target completed (Focus Field 22, HIP 108888)
21:16:14     Target Started (1/33) Target started (1/33, NGC 6627 w/AT2021abkm)
21:23:33       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
21:25:24       Focusing Completed Foc1 AutoFocus Completed (Profile No 3)
21:42:06     Target Completed Target completed (1/33, NGC 6627 w/AT2021abkm)
21:42:09     Target Started (2/33) Target started (2/33, NGC 6184 w/SN2021wkv)
21:50:16   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars)
21:50:31   SoftSuspend Cancelled Soft Suspend is cancelled due to Improved Conditions
21:54:31   Dome Closed Dome closed (closing time 45s)
21:54:34     Target Aborted (2/33) Target aborted (2/33, NGC 6184 w/SN2021wkv) due to other condition
21:54:36   Queue Paused Queue paused for Session Suspension
21:54:39 Session Suspended Session suspended
21:54:41   Dome Closed Dome already closed (closed at 21:54, closing time 45s)
21:56:34     Target Cancelled Target cancelled (2/33, NGC 6184 w/SN2021wkv) due to light conditions
21:56:42 Session Resuming Session resuming
21:58:22 Session Suspended Session suspended
21:58:24   Dome Closed Dome already closed (closed at 21:54, closing time 45s)
22:00:27 Session Resuming Session resuming
22:00:42   Dome Closed Dome closed (closing time 10s)
22:01:02   Dome Closed Dome closed (closing time 10s)
22:02:07 Session Suspended Session suspended
22:02:09   Dome Closed Dome already closed (closed at 22:01, closing time 10s)
22:04:12 Session Resuming Session resuming
22:04:32   Dome Closed Dome closed (closing time 5s)
22:04:42   Dome Closed Dome closed (closing time 5s)
22:05:53 Session Suspended Session suspended
22:05:55   Dome Closed Dome already closed (closed at 22:04, closing time 5s)
22:07:58 Session Resuming Session resuming
22:08:08     Target Cancelled Target cancelled (3/33, GCVS Z And) due to light conditions
22:08:18   Dome Closed Dome closed (closing time 10s)
22:08:20 User Intervention User Intervention to regain control after race condition between AstroMain & AstroGuard
22:08:25   Queue Aborted Job Queue aborted
22:08:28 Session Closing Session closing
22:08:33   Dome Closed Dome already closed (closed at 22:08, closing time 10s)
22:09:50   Dome Parked Dome parked (parking time 69s), Az: 90.0 deg
22:11:20   Telescope Parked Telescope parked (parking time 83s)
22:11:35   Telescope State Scope parked Turn scope off. (Handbox)
22:11:55   Telescope Switched Off Telescope Power has been switched off via UPB Switch.
22:12:45   Services Stopped Night Services stopped
22:12:47 Session Housekeeping Housekeeping Started (Cleanup FITS, Create Fits Summary, Transfer Files)
22:12:53 Session Finished Session Finished
22:21:46 Session Resumed Live Session Resumed (2021-10-22 S00926, ImageSaveNum: 926014)
22:22:09   Obs.Manager Started Obs.Manager started
22:22:11   Obs.Overseer Started Obs.Overseer started
22:22:16   Services Started Observatory Services started
22:23:15   Dome Opened Dome opened (opening time 43s)
22:27:40 Critical Light Alert Critical Light Alert (Obs.Manager will close the Shutter)
22:28:30   Dome Closed Dome closed (closing time 50s)
22:29:37 Session Monitoring AutoStart monitoring for Live Session opportunity between 22:29 & 05:54
22:29:39 Observatory (AutoStart) Observatory placed in Auto-Start Mode
22:29:40   AutoStart Delayed Session delayed due to too few stars
22:30:20 Session AutoStarting Session autostarting (22:30)
22:30:41   Scope Switched On Telescope Power has been switched on via UPB Powerbox.
22:32:27   Services Started Observatory Services started
22:32:33 Observatory (Auto) Observatory placed in Fully-Automated Mode
22:32:36 Session Pending Session pending (2021-10-22)
22:32:38 Session Initiating Session initiating (2021-10-22)
22:32:40   Plan Requested Observing Plan requested from AstroPlan (1.26)
22:35:06   Plan Loaded Observing Plan loaded to queue (, Plan ID: 677)
22:35:17   Camera1 Connected SBIG Camera Connected (set point -20°C)
22:35:23   Telescope Connected Telescope Connected (TheSky6)
22:35:47 Session Equilibration Session ready for dome & camera equilibration
22:36:32   Dome Opened Dome opened (opening time 45s)
22:36:34 Session Running Session running
22:36:36   Queue Started Observing Queue started (32 targets selected)
22:36:39     Target Started (1/32) Target started (1/32, NGC 6184 w/SN2021wkv)
22:56:35     Target Completed Target partially completed (1/32, NGC 6184 w/SN2021wkv)
22:56:38     Target Started (2/33) Target started (2/33, GCVS Z And, ToO)
23:00:15       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
23:02:35       Focusing Completed Foc1 AutoFocus Completed (Profile No 6)
23:07:43     Target Completed Target completed (2/33, GCVS Z And, ToO)
23:07:45     Target Started (3/34) Target started (3/34, WDS GRB 34, ToO)
23:10:48       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
23:13:01       Focusing Completed Foc1 AutoFocus Completed (Profile No 7)
23:15:03     Target Completed Target completed (3/34, WDS GRB 34, ToO)
23:15:05     Target Missed (4/34) Target's time slot was missed (4/34, NGC 6627 w/AT2021abkm)
23:16:26     Target Started (5/34) Target started (5/34, GCVS BL Lac)
23:21:50       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
23:24:09       Focusing Completed Foc1 AutoFocus Completed (Profile No 8)
23:28:21     Target Completed Target completed (5/34, GCVS BL Lac)
23:28:23     Target Started (6/34) Target started (6/34, GCVS Z And)
23:31:28       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
23:33:47       Focusing Completed Foc1 AutoFocus Completed (Profile No 9)
23:38:52     Target Completed Target completed (6/34, GCVS Z And)
23:38:54     Target Started (7/34) Target started (7/34, GCVS RX And)
23:41:38       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
23:43:51       Focusing Completed Foc1 AutoFocus Completed (Profile No 10)
23:47:13     Target Completed Target completed (7/34, GCVS RX And)
23:47:16     Target Started (8/34) Target started (8/34, GCVS HH And)
23:49:47       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
23:52:06       Focusing Completed Foc1 AutoFocus Completed (Profile No 11)
23:54:10     Target Completed Target completed (8/34, GCVS HH And)
23:54:13     Target Started (9/34) Target started (9/34, M31 w/AT2021aaxp)
23:57:12       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
23:59:13       Focusing Completed Foc1 AutoFocus Completed (Profile No 12)
00:01:59   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars)
00:02:45   SoftSuspend Cancelled Soft Suspend is cancelled due to Improved Conditions
00:05:37     Target Completed Target completed (9/34, M31 w/AT2021aaxp)
00:05:39     Target Started (10/34) Target started (10/34, Vega)
00:10:09     Target Completed Target completed (10/34, Vega)
00:11:03     Target Started (11/34) Target started (11/34, GCVS RR Lyr)
00:15:11       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
00:17:33       Focusing Completed Foc1 AutoFocus Completed (Profile No 13)
00:26:24     Target Completed Target completed (11/34, GCVS RR Lyr)
00:26:26     Target Started (12/34) Target started (12/34, Vega)
00:31:32     Target Completed Target completed (12/34, Vega)
00:31:35     Target Started (13/34) Target started (13/34, AT2021zkf)
00:34:34       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
00:36:32       Focusing Completed Foc1 AutoFocus Completed (Profile No 14)
00:48:34   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (too few stars)
00:52:59     Target Completed Target completed (13/34, AT2021zkf)
00:53:01   Queue Paused Queue paused for Session Suspension
00:53:03 Session Suspended Session suspended
00:53:49   Dome Closed Dome closed (closing time 50s)
01:08:10     Target Cancelled Target cancelled (14/34, GCVS SS Cyg) due to other condition
01:20:39     Target Cancelled Target cancelled (15/34, Nova Cas 2021) due to cloud
01:40:01     Target Cancelled Target cancelled (16/34, NGC 9 w/SN2021zju) due to cloud
02:01:53     Target Cancelled Target cancelled (17/34, UGC 235 w/AT2021aazm) due to cloud
02:23:05     Target Cancelled Target cancelled (18/34, 67P/Churyumov-Gerasimenko) due to cloud
02:32:16     Target Cancelled Target cancelled (19/34, GCVS GK Per) due to cloud
02:45:49     Target Cancelled Target cancelled (20/34, 10P/Tempel) due to cloud
02:59:41     Target Cancelled Target cancelled (21/34, AT2021wuy (CV)) due to cloud
03:11:13     Target Cancelled Target cancelled (22/34, GSC 1224:29) due to cloud
03:13:47 Session Resuming Session resuming
03:14:32   Dome Opened Dome opened (opening time 45s)
03:14:34 Session Running Session running
03:14:36   Queue Resumed Observing Queue resumed
03:14:38     Target Started (23/34) Target started (23/34, GCVS FO Ori)
03:20:33       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
03:22:58       Focusing Completed Foc1 AutoFocus Completed (Profile No 15)
03:26:08     Target Completed Target partially completed (23/34, GCVS FO Ori)
03:26:10     Target Started (24/34) Target started (24/34, AT2021xmw)
03:29:02       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
03:30:59       Focusing Completed Foc1 AutoFocus Completed (Profile No 16)
03:44:39     Target Completed Target partially completed (24/34, AT2021xmw)
03:44:41     Target Started (25/34) Target started (25/34, UGC 3240 w/SN2021vau)
03:47:46       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
03:49:34       Focusing Completed Foc1 AutoFocus Completed (Profile No 17)
04:06:29     Target Completed Target completed (25/34, UGC 3240 w/SN2021vau)
04:06:31     Target Started (26/34) Target started (26/34, 88P/Howell)
04:11:58       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
04:14:33       Focusing Completed Foc1 AutoFocus Completed (Profile No 18)
04:25:01     Target Completed Target partially completed (26/34, 88P/Howell)
04:25:03     Target Started (27/34) Target started (27/34, C/2019 L3 (ATLAS))
04:27:33       Focusing Skipped Foc1 focusing skipped - star is too dim (TCF-S)
04:35:39     Target Completed Target completed (27/34, C/2019 L3 (ATLAS))
04:35:42     Target Started (28/34) Target started (28/34, GCVS DX Cnc)
04:37:50       Focusing Skipped Foc1 focusing skipped - star is too dim (TCF-S)
04:42:41     Target Completed Target completed (28/34, GCVS DX Cnc)
04:46:04     Target Started (29/34) Target started (29/34, LAMOST-HVS1)
04:50:47       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
04:52:45       Focusing Completed Foc1 AutoFocus Completed (Profile No 19)
04:56:42     Target Completed Target completed (29/34, LAMOST-HVS1)
04:56:45     Target Started (30/34) Target started (30/34, UGC 5994 w/AT2021ably)
05:02:05       Focusing Skipped Foc1 focusing skipped - star is lost (TCF-S)
05:18:07     Target Completed Target completed (30/34, UGC 5994 w/AT2021ably)
05:18:09     Target Started (31/34) Target started (31/34, C/2021 A1 (Leonard))
05:23:48       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
05:25:49       Focusing Completed Foc1 AutoFocus Completed (Profile No 20)
05:36:41     Target Completed Target completed (31/34, C/2021 A1 (Leonard))
05:36:43     Target Started (32/34) Target started (32/34, UGC 5751 w/AT2021abcw)
05:41:29       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
05:43:52       Focusing Completed Foc1 AutoFocus Completed (Profile No 21)
06:00:24     Target Completed Target completed (32/34, UGC 5751 w/AT2021abcw)
06:00:26     Target Started (33/34) Target started (33/34, Nova Per 2020)
06:04:55       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
06:06:53       Focusing Completed Foc1 AutoFocus Completed (Profile No 22)
06:15:51     Target Completed Target completed (33/34, Nova Per 2020)
06:15:53     Target Started (34/34) Target started (34/34, 17P/Holmes)
06:18:38       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
06:20:48       Focusing Completed Foc1 AutoFocus Completed (Profile No 23)
06:31:39     Target Completed Target completed (34/34, 17P/Holmes)
06:31:40   Queue Completed Job Queue completed
06:31:45 Session Closing Session closing
06:32:40   Dome Closed Dome closed (closing time 50s)
06:33:55   Dome Parked Dome parked (parking time 68s), Az: 90.0 deg
06:35:10   Telescope Parked Telescope parked (parking time 67s)
06:35:26   Telescope State Scope parked Turn scope off. (Handbox)
06:35:46   Telescope Switched Off Telescope Power has been switched off via UPB Switch.
06:36:37   Services Stopped Night Services stopped
06:36:39 Session Housekeeping Housekeeping Started (Cleanup FITS, Create Fits Summary, Transfer Files)
06:37:06 Session Finished Session Finished
 
Session Alerts
Time     Alert Detail
21:53:46 Unexpected Dome Closure Dome is unexpectedly closing (Good Conditions)
22:00:42 Dome Discrepency Hub reports Dome is Closed, but Dome reports it is Opening
22:00:52 Unexpected Dome Closure Dome is unexpectedly closing (Good Conditions)
22:04:37 Unexpected Dome Closure Dome is unexpectedly closing (Good Conditions)
22:37:31 Dome Discrepency Difference between Telescope Az and Dome Az is > 8 deg (NGC 6184)

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Operational Issues (2021-10-22, S926)

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Critical Issues

Major Issues

Minor Issues

Small Defects

Continuous Improvement

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2021-10-23


Daytime Tests - Examination of IR Leakage from Observatory WebCam

ObsCam
ObsCam is an observatory web cam which operates 24x7 and provides a realtime view of the interior of the observatory and of the telescope in particular. In low light conditions (when observatory is shut or at night time)  the webcam automatically switches on its IR LED Lights to provide sufficient light for b/w night vision. 

Potential IR leakage during Imaging
During an observing session the ObsCam view of the telescope is useful for recording  & diagnosing any issues with the telescope movements or resolving an ambiguities over the telescope position and operations.    The IR lights that are used to illuminate the interior of the observatory for the webcam viewing however has the potential of straying on the sensitive CCD chip in the SBIG ST-10XME camera that is attached to the telescope. This could occur through reflection into the front of the telescope or via any leakage path at the back of the telescope or back of SBIG camera.  Issues with stray light have seen and previous tests showed that the IR leakage was large via the TCF-S focuser (see  ObsCam - IR leakage onto CCD Images (tests and solution, 2021-04-15).  Entry of reflected IR light through front of telescope, and entry of direct IR light through the back of the camera were ruled out. The IR leakage problem was mitigated by wrapping a jumper around the focuser and the tube attachment to the camera.   

This mitigation has generally been successful in cutting down on stray IR light however it has been perceived that there are certain telescope positions where some stray IR light was still getting onto CCD Images.   This was highlighted by a set of 180s exposures from Target 'NGC 514 w/SN' in session S921 (2021-10-04) taken at Az 166.7° / Alt 45.1° where was a distinct stray light artifact along the top of raw frames (internal reflection from guide chip mirror ?) .  See picture below.

Image
CCD Image  (50% size, linear scale)
5 x 180s exposure (average combine), 3x3 binning, C Filter
2021-10-05 00:11 UT (#921139-43)
12" LX200R (at f/10.4) + ST-10XME
Auto-guided using TS 80mm APO, ZWO ASI178MC & PHD2

AllSky Measurements & AllSky pictures show clear very dark skies at the target location with no indication of any bright light source shinning towards the observatory, whilst ObsCam pictures show the back of the CCD Camera lit up by the IR light. So it would seem that the stray light is IR light from WebCam coming into the camera via a leak path at the back of camera. 

Image Image

The following photo was accidently taken in the observatory on another occasion. The camera was moving for part of the exposure, but it makes quite an interesting shot. Looking like a jellyfish the IR Led lights associated with the ObsCam (not really visible with naked eye) are nicely highlighted in the photo.  It is the light from these IR Leds that is straying onto CCD Images.

Image

 

Daytime Tests (2021-10-23)
Telescope was turned on,  then slewed to Az 166.7° / Alt 45.1° which was the position that NGC 514 target suffered a stray light artifact in session S921.   Telescope tracking was turned off to keep the scope located on this specific position for Test 1a and 1b.

The results show that peak leakage is occuring at Alt 45° and Az 175-180°. See picture below :

Image

The region affected by some IR leakage appears to be a rectangular region 30° wide and 8° high (Az 160° - 190°,  Alt 40° -  47°)
 

The Observatory has now been programmed to automatically turn off the ObsCam whilst recording images from each target. (2021-10-23) which will prevent the possibility of any stray IR light reaching the CCD Camera in future.

Next Steps

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