David's Astronomy Pages
Notes - Session 1048 (2022-10-22)

 
Bullet Session Aims & Highlights
 - Observing Result
 - Night Summary Plot
 - Session Event Log
Bullet Operational Issues
  - Critical Issues (0),  Major Issues (2),  Minor Issues (8),  Small Defects (5),  Continuous Improvement (16)
 
Bullet Images from 2022-10-22 >>        [ Local Files >> ]    
Bullet Nedis 4-Button Remote Controller (Zigbee)
Bullet deCONZ - WebSocket Configuration
Bullet deCONZ - WebSocket Listener
Bullet AllSky Camera - Dew Problem (2022-10-16 to 2022-10-23)
   

Session Aims & Highlights (2022-10-22)

Main aims

  1. Zigbee Network: Conduct first live session test using newly introduced Zigbee Network. Check for any issues. Identify any improvements.
  2. AstroMain.  Check new AstroMain version (3.56.1) for any issues introduced by recent changes and additions.
  3. Targets.  Acquire images of a selection of variable stars, nearby stars, comets & deep sky targets as allowed by sky conditions.
  4. Observatory Alarms.  Check out use of Chrome/Chromecast to send audio messages and alarms through to Google Home speaker. .

 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
Image
Image   
  
Session Event Log
Time     Event Detail
23:38:09 Session Monitoring AutoStart monitoring for Live Session opportunity between 23:38 & 05:58
23:38:13   AutoStart Delayed Session delayed due to too few stars
23:38:28 Session AutoStarting Session autostarting (23:38)
23:38:54   SBIG Camera Reset SBIG Camera being power-cycled to fix locked threads issue
23:39:21 Session Created Session Created (Live, 2022-10-22 S01048, ImageSaveNum: 1048001)
23:39:24   Scope Switched On Telescope Power has been switched on via UPB Powerbox.
23:41:01   CCDSoft Restarting CCDSoft being killed and restarted in attempt to fix locked threads
23:41:07   SBIG Camera Reset SBIG Camera being power-cycled to fix locked threads issue
23:41:09   Services Started Observatory Services started
23:41:16 Observatory (Auto) Observatory placed in Fully-Automated Mode
23:41:18 Session Pending Session pending (2022-10-22)
23:41:20 Session Initiating Session initiating (2022-10-22)
23:41:22   Plan Requested Observing Plan requested from AstroPlan (1.32.6)
23:42:03   Plan Loaded Observing Plan loaded to queue (Plan ID: 810)
23:42:14   Camera1 Connected SBIG Camera connected (set point -10°C)
23:42:20   Telescope Connected Telescope connected (TheSky6)
23:42:23 Obs.Monitor Frozen Obs.Monitor appears to be frozen at around 23:42 in section Update Foc1 Fields
23:42:44 Session Equilibration Session ready to Open Dome
23:44:24   Wait On Weather Waiting for acceptable conditions
23:44:26 Session Suspended Session suspended
23:44:28   Dome Closed Dome already closed
23:44:30   Queue Started Observing Queue started (23 targets selected)
23:44:40   CCDSoft Restarting CCDSoft being killed and restarted in attempt to fix locked threads
23:44:46   SBIG Camera Reset SBIG Camera being power-cycled to fix locked threads issue
23:45:24   Camera1 Connected SBIG Camera connected (set point -10°C)
23:46:29 Session Resuming Session resuming
23:47:15   Dome Opened Dome opened (opening time 45s)
23:47:17 Session Running Session running
23:47:19   Queue Resumed Observing Queue resumed
23:47:21     Target Started (NrZen) Target started (Focus Field 1, HIP 4911)
23:47:31   Dome Unparked Dome unparked
23:51:58       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
23:54:21       Focusing Completed Foc1 AutoFocus Completed (Profile No 1, wide)
23:56:17       Focusing Completed Foc1 AutoFocus Completed (Profile No 1)
23:56:42       Focusing Started-Foc2 Foc2 Focusing Started (Secondary Scope, using ShCap)
23:58:50       Focusing Completed Foc2 AutoFocus Completed (Profile No 2, wide)
00:00:33       Focusing Completed Foc2 AutoFocus Completed (Profile No 2)
00:00:50     Target Completed (NrZen) Target completed (Focus Field 1, HIP 4911)
00:00:54     Target Started (1/23) Target started (1/23, GCVS BL Lac)
00:04:40       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
00:06:42       Focusing Completed Foc1 AutoFocus Completed (Profile No 3)
00:10:46     Target Completed Target completed (1/23, GCVS BL Lac)
00:10:50     Target Started (2/23) Target started (2/23, Jupiter)
00:13:35     Dome Slew Dome slew held up at Az. 246.3, 222.3, 221.5, 220.4° (Total delay 127s)
00:20:13     Target Completed Target completed (2/23, Jupiter)
00:20:17     Target Started (3/23) Target started (3/23, NGC 7448 w/SN2022wsp)
00:24:25       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
00:26:36       Focusing Completed Foc1 AutoFocus Completed (Profile No 4)
00:42:22     Target Completed Target completed (3/23, NGC 7448 w/SN2022wsp)
00:42:26     Target Started (4/23) Target started (4/23, NGC 7495 w/SN2022ubb)
00:46:16       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
00:48:13       Focusing Completed Foc1 AutoFocus Completed (Profile No 5)
01:04:24     Target Completed Target completed (4/23, NGC 7495 w/SN2022ubb)
01:04:28     Target Started (5/23) Target started (5/23, NGC 157 w/SN2022jli)
01:05:44     Dome Slew Dome slew held up at Az. 221.5° (Delay 49s)
01:19:59   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (reducing clarity)
01:20:04   Critical Cloud Alert Critical Cloud Alert (Obs.Manager will close the Dome)
01:20:06   HardSuspend Called Hard Suspend is called due to Critical Conditions (cloud)
01:20:10     Target Aborted (5/23) Target aborted (5/23, NGC 157 w/SN2022jli) due to cloud
01:20:13   Queue Paused Queue paused for Session Suspension
01:20:14 Session Suspended Session suspended
01:20:59   Dome Closed Dome closed (closing time 45s)
01:22:18     Target Cancelled Target cancelled (5/23, NGC 157 w/SN2022jli) due to cloud
01:44:18     Target Cancelled Target cancelled (6/23, NGC 873 w/SN2022xjk) due to cloud
02:06:18     Target Cancelled Target cancelled (7/23, UGC 2508 w/AT2022trp) due to other condition - Blank
02:06:20 Session Resuming Session resuming
02:07:03   Dome Opened Dome opened (opening time 45s)
02:07:05 Session Running Session running
02:07:07   Queue Resumed Observing Queue resumed
02:09:22     Target Started (8/23) Target started (8/23, C/2020 V2 (ZTF))
02:13:30       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
02:15:46       Focusing Completed Foc1 AutoFocus Completed (Profile No 6)
02:34:06     Target Completed Target completed (8/23, C/2020 V2 (ZTF))
02:34:10     Target Started (9/23) Target started (9/23, NGC 3938 w/SN2022xlp)
02:37:08       Focusing Skipped Foc1 focusing skipped - star is too dim (TCF-S)
02:53:30     Target Completed Target completed (9/23, NGC 3938 w/SN2022xlp)
02:53:43     Target Started (10/23) Target started (10/23, GCVS SS Cyg)
02:57:04       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
02:59:08       Focusing Completed Foc1 AutoFocus Completed (Profile No 7)
03:03:15     Target Completed Target completed (10/23, GCVS SS Cyg)
03:09:57     Target Started (11/23) Target started (11/23, AT2022why)
03:13:29       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
03:15:28       Focusing Completed Foc1 AutoFocus Completed (Profile No 8)
03:21:48     Target Completed Target completed (11/23, AT2022why)
03:21:52     Target Started (12/23) Target started (12/23, AT2022weo)
03:24:45   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (reducing clarity)
03:24:47   Critical Cloud Alert Critical Cloud Alert (Obs.Manager will close the Dome)
03:24:49   HardSuspend Called Hard Suspend is called due to Critical Conditions (cloud)
03:24:51     Target Aborted (12/23) Target aborted (12/23, AT2022weo) due to cloud
03:24:53   Queue Paused Queue paused for Session Suspension
03:24:55 Session Suspended Session suspended
03:25:40   Dome Closed Dome closed (closing time 50s)
03:32:53     Target Cancelled Target cancelled (12/23, AT2022weo) due to cloud
03:55:43     Target Cancelled Target cancelled (13/23, AT2022kl (CV)) due to cloud
04:04:41     Target Cancelled Target cancelled (14/23, GCVS HH And) due to cloud
04:12:44     Target Cancelled Target cancelled (15/23, WDS GRB 34) due to cloud
04:13:30 Session Resuming Session resuming
04:14:15   Dome Opened Dome opened (opening time 45s)
04:14:17 Session Running Session running
04:14:19   Queue Resumed Observing Queue resumed
04:14:22     Target Started (16/23) Target started (16/23, NGC 5894 w/SN2022pgf)
04:14:24   SoftSuspend Called Soft Suspend is called due to Deteriorating Conditions (reducing clarity)
04:16:20   SoftSuspend Cancelled Soft Suspend is cancelled due to improved conditions
04:19:24       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
04:22:01       Focusing Completed Foc1 AutoFocus Completed (Profile No 9)
04:38:35     Target Completed Target completed (16/23, NGC 5894 w/SN2022pgf)
04:38:39     Target Started (17/23) Target started (17/23, UGC 3923 w/SN2022rqc)
04:39:18   Dome Unparked Dome unparked
04:41:49       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
04:44:16       Focusing Completed Foc1 AutoFocus Completed (Profile No 10)
05:00:46     Target Completed Target completed (17/23, UGC 3923 w/SN2022rqc)
05:00:50     Target Started (18/23) Target started (18/23, AT2022vxe)
05:20:40     Target Completed Target completed (18/23, AT2022vxe)
05:20:44     Target Started (19/23) Target started (19/23, AT2022whd (CV))
05:23:31       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
05:25:28       Focusing Completed Foc1 AutoFocus Completed (Profile No 11)
05:31:47     Target Completed Target completed (19/23, AT2022whd (CV))
05:31:51     Target Started (20/23) Target started (20/23, AT2022qnv)
05:36:05       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
05:38:17       Focusing Completed Foc1 AutoFocus Completed (Profile No 12)
05:54:03     Target Completed Target completed (20/23, AT2022qnv)
05:54:07     Target Started (21/23) Target started (21/23, AT2022tqu)
05:59:26       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
06:01:41       Focusing Completed Foc1 AutoFocus Completed (Profile No 13)
06:17:30     Target Completed Target completed (21/23, AT2022tqu)
06:17:34     Target Started (22/23) Target started (22/23, GCVS SY Cnc)
06:20:55       Focusing Skipped Foc1 focusing skipped - star is too dim (TCF-S)
06:24:16     Target Completed Target completed (22/23, GCVS SY Cnc)
06:24:20     Target Started (23/23) Target started (23/23, GCVS GK Per)
06:28:03       Focusing Started-Foc1 Foc1 Focusing Started (TCF-S)
06:30:16       Focusing Completed Foc1 AutoFocus Completed (Profile No 14)
06:33:38     Target Completed Target completed (23/23, GCVS GK Per)
06:33:41   Queue Completed Job Queue completed
06:33:44 Session Closing Session closing
06:34:34   Dome Closed Dome closed (closing time 45s)
06:36:00   Dome Parked Dome parked (parking time 79s), Az: 90.0 deg
06:37:13   Telescope Parked Telescope parked (parking time 69s)
06:37:28   Telescope State Scope parked Turn scope off. (Handbox)
06:37:50   Telescope Switched Off Telescope Power has been switched off via UPB Switch.
06:38:46   Services Stopped Night Services stopped
06:38:48 Session Housekeeping Session Housekeeping started (Create Fits Summary, Transfer Files)
06:39:09 Session Finished Session Finished
 
Session Alerts
Time     Alert Detail
23:42:53 Obs.Monitor Obs.Monitor appears to be frozen in section Update Foc1 Fields (last cycle at 23:42:23)
23:44:43 Obs.Monitor Obs.Monitor has resumed again after 2.3 mins
 

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Operational Issues (2022-10-22, S1048)

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Critical Issues

Major Issues

Minor Issues

Small Defects

Continuous Improvement

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Nedis 4-Button Remote Controller (Zigbee)

A 4-button remote controller or key fob (NEDIS ZBRC10WT Smart Remote Controller, 6.6cm x 3.4cm x 1.2cm in size, CR 2032 battery) has been ordered from Amazon on 2022-10-19 (https://www.amazon.co.uk/dp/B087QSD3VC/ref=pe_27063361_485629781_TE_item ) for delivery around 2022-11-01. Consideration will be given to a number of ideas about how the remote controller will be used for operation of the observation.  

Upon arrival the remote controller will be installed on the Observatory's zigbee network. It is understood that switch/button type devices will be installed as sensors of type ZHASwitch, but that remains to be confirmed.  There is a risk that the controller is difficult or impossible to install or operate on the DeCONZ / Phoscon based network.

It is probable that button events will need to be read by means of a Net Socket rather than using REST API's

Switches are supported as one or more /sensors resources of type ZHASwitch (or ZGPSwitch for Zigbee Green Power switches), with events with the syntax is X00Y, where X is the button number and Y is the event   https://github.com/dresden-elektronik/deconz-rest-plugin/wiki/Supported-Devices#events-legend.
For most switches, the value of state.buttonevent indicates how the switch was operated (X indicates the button): 

Value Action
 0  x000   Initial Press
 1  x001   Hold
 2  x002  Release (after press)
 3  x003  Release (after hold)
 4  x004  Double press
 5  x005  Triple press
 6  x006  Quadruple press
 7  x007  Shake
 8  x008  Drop
 9  x009  Tilt
 10 x010  Many press

Update 2022-11-01
An attempt was made to install the Nedis Remote Controller (key fob) onto the Observatory Zigbee Network.  Attempts to install the Nedis device using the the Add Sensor/Search dialog in the Phoscon App failed (search for sensor timed-out having appeared not to have found or recognised the device). This was tried several times, taking care to reset the device, but in the end had to concede defeat.

Despite the apparent installation failure in Phoscon it was later noticed that a new end-device had in fact appeared in the Network map in deCONZ.  
with name '0x7CED' and type 'IAS Ancillary Control Equipment'.   The was no sign of the device using REST-API calls to get full state or get sensors.

Later on after a WebSockets client had been built to get push notifications from the WebSocket Server in deCONZ's REST-API plug-in , it was noted that button presses on the Nedis remote controller didn't produce any websocket messages. However the same button presses did cause the devices's top-left indicator (in the deCONZ network window) to momentarily light up blue. The latter indicates that the remote controller is functioning and in communication with the Conbee II.

Update 2022-11-09
A fresh attempt was made to access/integrate the Nedis Remote Controller (key fob)

Again it was confirmed the button presses on the remote controller caused momentary blue lights to appear in the deCONZ window and that the button presses were still not causing any notifications to be recieved over websocket (websocket was definately working as notications for other devices were being recieved ok).

REST-API document provides information regarding alarm systems and keypads, from which it was gleaning that rest api information could be obtained for a sensor using the device's unique id instead of its internal number.

Tried
  GET api/{{ApiKey}}/sensors/{{unique_id}}
      where {{ApiKey} is the api key for accessing the network via REST API
      and {{unique_id}} is the device's unique_id.  

Since the remote controller couldn't be seen in response to either
   GET api/{{ApiKey}}  or  
    GET api/{{ApiKey}}/sensors

it was difficult to know definitively what its unique_id was however it almost certainly starts with its MAC address which is known from device's Node Info panel in deCONZ.

But using    GET api/{{ApiKey}}/sensors/bc:33:ac:ff:fe:61:a0:af
gave the 404 Not Found response  with type 3 error 'resource not found'

Next attempt was to try guessing the suffix at the end of the unique_id.  The 4 Hue Smart Plugs in the Observatory Newtork each have a unique_id  suffix of '-0b'   whilst the two open/close sensors both have suffix '-01-0006'.  Whilst the '-0b' suffix for hue smart plugs possibly related to the device's Manufacturer Code 0x100b      ie 0b. it was clear where the suffix for open/close sensors originated.

 

Keyfob nedis model. TS0215A 4button device handler?
https://community.smartthings.com/t/keyfob-nedis-model-ts0215a-4button-device-handler/235708  and
https://gist.github.com/nksglns/a0cc110f87233ba0da809ec5b1ce7e44

https://github.com/Koenkk/zigbee2mqtt/issues/13159



Indicates

manufacturer: "_TZ3000_p6ju8myv"     or _TZ3000_tj4pwzzm
model: "TS0215A", or "TS0215A_remote"

This offers the possibility of using DDF Editor to create a json file to define the device

AlarmSystems

I wondered if the Remote Controller needed to be connected to an alarm system before it would became visible ?

so tried assigning the Nedis remote controller to alarmsystem 1 using
   PUT api/{{ApiKey}}/alarmsystems/1/device/bc:33:ac:ff:fe:61:a0:af
    { }
but this failed with type 4 error "PUT not available for resource \ /alarmsystems\ /1\ /bc:33:ac:ff:fe:61:a0:af"
It is possible that this fails because the unique_id is not complete or not recognised in the REST API environment (even though device is present in the deCONZ Network Map.)

Prehaps the alarm system needs to be 'configured' before it would accept a device so tried to set its code0 with the following command
  PUT api/{{ApiKey}}/alarmsystems/1/config
   {"code0": "12345" }
but this failed success with type 901 error "internal error 'failed to set code' occurred.

This seems a issue with setting up/saving encryted code0 value,  since the following command to change one of the other alarms configuration parameters
  PUT api/{{ApiKey}}/alarmsystems/1/config
   {"armed_night_trigger_duration": 130}
was successfully achieved

Tried creating a new alarm system using
   POST api/{{ApiKey}}/alarmsystems
   { "name": "ObsAlarm"}

but this gave the a 501 error  with message "Unimplemented",  which is consistent with REST-API documentation on 'Create Alarm System' which says that the request is 'Not Implemented'.

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deCONZ - WebSocket Configuration

deCONZ has an embedded Websocket server that provides push notifications to applications which require real-time feedback from devices like lights, groups, switches, and sensors.  (https://dresden-elektronik.github.io/deconz-rest-doc/endpoints/websocket/)

The Websocket server is started on an unused proxy friendly port which, depending on the system, is either 443, 8080, 8088, 20877, or any other unused random port.
and can be configured to include all state or config attributes in the message, or only the changed attributes.

The Websocket used port and setting are listed in the configuration API endpoint:
GET /api/<apikey>/config

Values are currently

 "websocketnotifyall": true,
"websocketport": 443,


The establishment of  a connection to deCONZ Websocket server depends on the underlying programming environment.

Javascript example¶
The following example demonstrates how to establish a connection with Javascript in a browser or NodeJS implementation.

const WebSocket = require('ws');

const host = '192.168.1.202';
const port = 8088;

const ws = new WebSocket('ws://' + host + ':' + port);

ws.onmessage = function(msg) {
console.log(JSON.parse(msg.data));
}

The method/code used in VB.Net will be different. The websocket connection and listener to GCN Network that is used in AstroVOE program might form the basis of code to be used in AstoMain for accessing events from deCONZ's websocket.

Format of some the relevant events that will be useful for the Observatory Automation are as follows:

Light state change example
{
  "e": "changed",
  "id": "1",
  "r": "lights",
  "state": {
    "bri": 1,
    "on": true,
    "x": 65279,
    "xy": [
      0.9961,
      0.9961
    ],
    "y": 65279
  },
  "t": "event",
  "uniqueid": "00:0b:57:ff:fe:9a:46:ab-01"
}

Sensor button event example¶
{
  "e": "changed",
  "id": "5",
  "r": "sensors",
  "state": {
    "buttonevent": 2002,
    "lastupdated": "2019-03-15T20:16:30"
  },
  "t": "event",
  "uniqueid": "00:0d:6f:00:10:65:8a:6e-01-1000"
}

Load Nugut Package - WebSocketForNet

From Visual Studio UI open the Nuget package manager console using the menu option 'Tools /Nuget Package Manager /Package Manager Console' and enter

    NuGet\Install-Package WebSocket4Net -Version 0.15.2

This was performed from a VS project called 'WebSockets' and the WebSocketForNet assembly was successfully installed and added as a Reference in the project's Solution.
From this a working prototype program to use WebSocket connection to the Observatory's Zigbee network was successfuly created.

However when the same command was used in the 'AstroMain' project the following error occurred

   NuGet\Install-Package : Package 'WebSocket4Net 0.15.2' is not found in the following primary source(s):
  'C:\Program Files (x86)\Microsoft SDKs\NuGetPackages\,C:\Data\Projects\Zigabee 

Investigating showed that the the Package installer had placed the WebSocket4Net assembly (plus an associated/dependant SuperSocket.ClientEngine assembly into the packages folder of the 'WebSockets' project

  C:\Users\David\Documents\Visual Studio 2022\Projects\WebSockets\packages

To get around this problem,  references to the WebSocket4Net assembly & SuperSocket.ClientEngine assemblies were manually added to the 'AstroMain' project using VS menu option 'Project /Add Reference/ Browse' and the two following paths :

To use the facilities provided by WebSockets4Net,  in a live setting the "WebSocket4Net.dll' and "SuperSocket.ClientEngine.dll"  files need to be manually copied to the
  'C:\Main Programs\AstroMain' folder on the Observatory Computer.

[ If this isn't done a  System.IO.FileNotFoundException arises "Could not load file or assembly 'WebSocket4Net, Version=0.15.2.11, Culture=neutral, PublicKeyToken=eb4e154b696bf72a' or one of its dependencies. The system cannot find the file specified" ]

 

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deCONZ - WebSocket Listener


Event Message associated wiith  "Switching On Aux Lights" :

 {"e":"changed","id":"2","r":"lights","state":{"alert":null,"on":true,"reachable":true},"t":"event","uniqueid":"00:17:88:01:09:d6:06:67-0b"}

Event Message associated with "Observatory Door opening"  :

 {"e":"changed","id":"5","r":"sensors","state":{"lastupdated":"2022-11-08T13:23:45.895","open":true},"t":"event","uniqueid":"00:15:8d:00:08:a5:94:a8-01-0006"}

It is noted that the message associated with a "ZHAOpenClose" sensor doesn't contain "reachable" , "battery" or "temperature" fields that requests through the deCONZ REST-API   provides. To get data on these extra fields suggests a requirement to make a REST-API request on a regular basis (say every 60s).


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AllSky Camera - Dew Problem (2022-10-16 to 2022-10-23)

Following an issue with earwigs crawling over AllSky Camera's fish eye lens and getting caught on camera (see AllSky Camera - Earwig Problem, 2022-10-16),  it was decided to unscrew the polycarbonate hemisphere covering the camera/camera lens and drop in some earwig/woodlice killing powder taking care not to get any of the powder on the fish-eye lens. The alternative would have been to remove the whole camera from its mast and open it up to remove the earwigs which would have been a more difficult process.  

Whilst the Insect killer seems to have resolved the problem (no earwigs seen in images over lthe following  6-7 days, the powder was put in on a very damp day, and it begun to rain lightly before the hemispshere could be put back on.  This led to the entrapment of high humidity air and possible some raindrop waters in the hemisphere when it was closed, and led to issue with very sigbificant dew formation on the inside surface of the polycarbonate hemisphere over the next 2 nights.

Image below was taken on the night of 2022-10-22.   Because the presence of the dew the sky view is very much affected.  The automated sky count saw a low star count (and the ones that were counted where potentially not real stars but artefact of the light pattern produced by the dew). The S1048 session had to be conducted without using the 'Too Few Stars' option which would normally be used and used by ObsManager to delay the opening of the dome or suspend the session when the numbers of stars dropped below a certain threshold.

Image   Image

Investigating the following day confirmed that dew in the form of large water drops was present on the inside surface of the hemisphere. The dew was present even though dew heater were on and clearly working (body of camera was warm to touch).

Image   Image

The hemisphere was wiped clear of water & dried, before reattached to the camera body.  Conditions were again very damp when this operation was conducted, humid air became trapped inside the camera and the following night dew (slightly finer droplets than before) again formed inside the hemisphere.

Again the hemisphere was wiped clear of water & dried, and then reattached.  This time the conditions were better, and this time lower humidity air was trapped inside the hemisphere. There was no problem with due on the folllowing two nights.

During the process of opening and removing the hemisphere it was noticed that the polycarbonate hemisphere was degraded, becoming less transparent , particularly in certain patched. Clearing didn't remove the marks.  It is unclear if patches of downgraded hemisphere is the result of bird-drops effecting the surface of the dome's polycarbonate hemisphere, or is due to unforeseen damaging effect from using a lens cleaner,

Clear Lesson:

Actions:

Update 2022-11-16
A replacement hemisphere was fitted to the AllSky camera on 2022-11-16 at 13:20 (outside humidity 75%, temperature 11degC). Three small desicator pouches (recently re-generated in a 110 degC oven) where packed around & below the fish-eye lens to maintain a dry atmosphere within the hemisphere, and the hemisphere screwed tighly down.

Picture :  TBA

Update 2023-01-25
A new O-Ring was installed in AllSky Camera that seems eventually to have resolved most of the dew problems (see AllSky Camera - New O-Ring, 2023-01-25).

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