Changes
SHOC
,/* Change Log */
'''Instrument software issues:''' Carel van Gend **050 (0768181312)
'''Telescope software issues:''' standby **113 (08290348690212015178) or 9118
'''Electronics Issues:''' standby **103 (07678951310212015179) or 9117
'''Mechanical Issues:''' standby **104 (076789512320212015180)
* Please report any problems on [https://faultreports.saao.ac.za/ the fault reports page].
== Introduction ==
The SHOC systems consist of a filterwheel unit (with one or two filterwheels), a GPS unit for providing accurate timing triggers, an Andor iXon camera, and a control PC. Currently there are 2 full SHOC systems (shocnawe & shocndisbelief), and 1 development system running a different camera (shocnhorror). As of March 2015, the control software is web-based. Users point their browser to the instrument location, and separate tabs appear to allow control of the camera, GPS, and filter wheel. SHOC can be mounted on the 1.9- and , 1-m and Lesedi telescopes. We have tried to make the usage telescope specific, but it is very useful to know which SHOC instrument is mounted on the telescope you are using. Details on instrument operation are below.
The [http://shoc.saao.ac.za SHOC website] may well have more extensive detail about this instrument.
* '''CONSIDER DECREASING DETECTOR TEMPERATURE IF TAKING LONG EXPOSURES''' Reports in 2016 indicated that the dark current is higher than expected (by a factor of ~ 100; more information to follow). This is most noticeable for long (>=10 minute) exposures. The camera is automatically cooled to -50C. It can be cooled down to -70 C; however, if the ambient temperature is high, the cooler will be stressed and cannot reach minimum temperatures. If you do adjust the temperature to -60, -65 or -70, please listen carefully so that if the temperature alarm triggers (a high-pitched, continuous beep) you can stop cooling and prevent hardware failure. March 2017
* '''THE NEW SOFTWARE HAS DIFFERENT FILE NAMES AND HEADER KEYWORDS THAN PREVIOUS DATA.''' If you use this information in your analyses, you will have to update it. The filename format has been standardized to <Instrument>_YYYYMMDD.####.fits, where the instrument is sha (shocnawe), shd (shocndisbelief), or SHH to designate which SHOC box is being used. Please check the header of a new data file or the wiki [http://topswiki.saao.ac.za/index.php/SHOC#FITS_Header_Keywords FITS header keywords] (the "new" keywords are directly from the Andor iXon camera under Linux). March 2015
* '''THE FILE SIZE IS NO LONGER LIMITED TO 2 GB. ''' This means that if you take large data cubes, the file size has ''no limit'' (this is because we are no longer on a Window-based, 32-bit, operating system). If you end up with a very large file, data analysis can be difficult. We are working on an efficient method to automatically split files into smaller sizes, but for now users need to be aware that requesting a large number of images in one file could return a very large file size (and if you mistakenly delete your file, you have lost alot of work!). It is recommended that multiple files be manually taken. ''If you have any questions or problems with the data, feel free to contact carel@ saao.ac.za or amanda@ saao.ac.za.'' March 2015
== Change Log ==
'''Most recent changes at the top'''
* '''Installation of "New" SHOC on the 74-inch, February 2024<br>'''
** Users should also familiarise themselves with these two wikis if they are using SHOC on the 74-inch after February 2024
** [https://topswiki.saao.ac.za/index.php/74%22_/_1.9m_-_%22Instrument_Selector%22 "Instrument Selector" wiki].
** [https://topswiki.saao.ac.za/index.php/%22New%22_SHOC "New" SHOC wiki].
* '''v1.4.4 Release date 5 December 2018<br>'''
== Quick Start ==
# Connect to the web browser. '''Go to http://shoc40in.suth.saao.ac.za:5000 or http://shoc74in.suth.saao.ac.za:5000 or http://shoclesedi.suth.saao.ac.za:5000 depending on which telescope you are using.'''# If you are prompted to log in, use the shoc74in or shoc40in or shoclesedi username and password, depending on which telescope you are using (passwords are the same as those used in the data transfer section, and should be obtained during startoff)
# Initialize the filter wheels and select your filter. '''You must initialize both filter wheels whenever the webservice is started.'''
# Click on camera tab: turn on the camera and confirm that it is cooling.
==Filter wheel==
* <span style="color: red">'''(1)'''</span> Point your browser at shoc40in.suth.saao.ac.za:5000 or shoc74in.suth.saao.ac.za:5000 or shoclesedi.suth.saao.ac.za:5000
'''NOTE: ON DNS ALIASES''': These telescope web addresses are aliases to the SHOC instruments. The real addresses for the instruments are shocnawe.suth.saao.ac.za:5000 or shocndisbelief.suth.saao.ac.za:5000. In order to avoid confusion, or the requirement that the user know which instrument is mounted on their telescope, we have created the aliases.
[[File:Filterwheel.png|1000px|left]]<br clear=all>
* Stop to abort <span style="color: red">'''(1)'''</span>, or wait until completion. The image display area (based on DS9) <span style="color: red">'''(2)'''</span> shows snapshots of the images throughout the acquisition.
* When the series is complete, the FITS data cube is copied to /data/<telescope>/<INSTR>/<YYYY>/<MMDD>/<filename>.fits, where:<br/>
:: '''<telescope>''' is 40in or 74inor lesedi,
:: '''<INSTR>''' could be shd for shocndisbelief, sha for shocnawe or shh for shocnhorror,
:: '''<YYYY>''' is the year,
=== Web interface===
* The primary means of controlling SHOC is via a web interface. The Firefox or Chrome browsers are preferred.
* Point your browser at http://shoc74in.suth.saao.ac.za:5000 or http://shoc40in.suth.saao.ac.za:5000 or http://shoclesedi.suth.saao.ac.za:5000
* If you are prompted to log in, use the shoc74in or shoc40in accounts depending on which telescope you are using.
* The interface should appear, showing three tabs: Filterwheel, GPS and Camera.
===LED timing tests===
''This functionality should be available on the 74", the 40" and the new 1mLesedi. It has only been tested on the 74".''
The idea is to take a long, GPS-triggered data cube with SHOC at high cadence, while running the LED at 1 PPS (which has a longer pulse on the minute and can thus be used to test absolute timing accuracy).
*The dome and mirror covers must be OPEN for this test to work. (The GPS needs to get satellite signal, and the LED must be seen through the light path.)
or
ssh shoc40in@shoc40in.suth.saao.ac.za
or ssh shoclesedi@shoclesedi.suth.saao.ac.za When prompted for the password, use the password for the 74in or 40in or lesedi user.
** In the terminal, type
restart_services
** Return to the web browser, and reload the page, then try to start the camera again.
** It may be necessary to restart the services a few times before you can start the camera.
* '''Acquisition doesn't start:''' Check on the GPS tab that the trigger signal has been activated. If it has, but the camera is still not taking images, try stopping the camera, resetting the GPS trigger to a time in the near future, and try again. Sometimes, it appears that the GPS trigger signal is not being sent (despite the software reporting that it is). The current acquisition should be stopped and restarted (because when the acquisition is started, the time the POP signal will start is recorded and will apear appear in the fits headers - so stopping and starting the acquisition will ensure that the correct POP time is used). Note that the index willl be incremented when doing this. To avoid this, you can rewind the increment by 1, in the advanced tab. Make sure you have no data that will be overwritten. *''' Acquisition doesn't finish:''' Sometimes it appears that the camera does not ever leave the acquiring state (despite all images in the kinetic series having been obtained). It may in this case be neccessary necessary to restart the server, manually edit the FITS files to include the filter and timing informationsinformation, and to then copy them to their final destination. The server may be restarted running the command "restart_services" from a terminal. The data is spooled to a directory under /data/spool/, based on the date, the sequence number and the time the acquisition started. In this directory is the data file, data.fits, and file containing other acquisition parameters, info.txt. The latter may be used to update the FITS header. The procedure is as follows:
** Rescue your data using the data rescue utility, as described in the section Rescuing Data.
** Run the command to restart the webserver, as described above in the subsection "Camera won't switch on".
or
ssh shoc40in@shoc74in.suth.saao.ac.za
or
ssh shoclesedi@shoclesedi.suth.saao.ac.za
When prompted for the password, use the password for the 74in or 40in user. Then go to the directory containing the spooled files:
cd /data/spool
sudo rescue_data.py
and then answer the questions as prompted. You'll be prompted for a password, use the password for the user you logged in as.
* The telescope is the name of the telescope being used; either 40in or , 74inor lesedi.
* The instrument will be one of shocnawe (sha) or shocndisbelief (shd). These are used to create the directory and filename in the /data directory. The directory will be of the form /data/<telescope>/<lowercase_instrument>/<YYYY>/<MMDD>, and the file of the form <instrument>_<YYYYMMDD>.<index>.fits. From this, the instrument name can be determined. At the moment, SHA is the SHOC instrument mounted on the 74inch and SHD is on the 40in.
* You will be prompted for an index to use. NB: '''make sure there is no existing file with the same index that will be overwritten''' The script will scan the target directory and list the existing files. Choose and index which isn't used(one option is to use an index like 3a , if index 3 exists). In other words, if files such as SHA_20150403.0004.fits and SHA_20150403.0005.fits, choosing either index 4 or 5 will result in that file being overwritten. If you choose as index 4a or 5a, the files will not be overwritten.
| 360
|-
| shoc1mshoclesedi.suth.saao.ac.za
| CNAME
| shocndisbelief.suth.saao.ac.za
|}
The shoc computer should be reachable by an '''alias''' containing the telescope name. Usually '''shoc74in''' is an alias to '''shocnawe''', and '''shoc40in''' is an alias to '''shocndisbelief'''. If, e.g. '''shocndisbelief''' is mounted on the '''74inch''' telescope, the alias '''shoc74in''' should be changed to point to '''shocndisbelief'''.
IT should '''ONLY''' change the '''CNAME record'''. The '''A records''' should '''NEVER''' change. Even if only one of the instruments is being moved to another dome, BOTH records must be switched or DNS resolution will be intermittent. Example of a switched DNS setup:
| 360
|-
| shoc1mshoclesedi.suth.saao.ac.za
| CNAME
| shocndisbelief.suth.saao.ac.za
|}
'''From'''
'''Note When You SSH After you ssh after the CNAME Changechange'''
Note: This change will result in a warning if someone tried to SSH into the machine - this is safe to accept.
Are you sure you want to continue connecting (yes/no)? yes
'''Possible CNAME Changeschanges'''
With the CNAME setup below, both the shocndisbelief and shocnawe can be connected in the new '''1m'''Lesedi. Please ask the IT standby person to help you with this DNS setup. At this moment '''only''' the '''shocnawe''' will be moved between the 40inch and 74inch. The '''shocndisbelief''' is in the '''1m''' and will '''not''' Either SHOC instrument may be moved between mounted on any of the 40inch and 74inchthree telescopes.
'''How It It Configured Nowto configure'''
{| class="wikitable" border="1"
|-
! TTL
|-
| shoc1mshoclesedi.suth.saao.ac.za
| CNAME
| shocndisbelief.suth.saao.ac.za
|}
'''Can Be Added If Requiredbe added if required'''
{| class="wikitable" border="1"
|-
! TTL
|-
| shoc1mshoclesedi.suth.saao.ac.za
| CNAME
| shocnawe.suth.saao.ac.za
|}
==Run the shocboxswitch.sh script when SHOC is moved between telescopes==
* Check the log entry to make sure the configuration was changed to the telescope you chose. In a terminal type:
less /var/log/shoc-camera.log
[[Fileimage:Camera-log.png|thumbnail500px]]
* Check and make sure that the configuration file points to the telescope name that you chose. In a terminal type:
less /etc/init/shoc-camera.conf
* Take test data to make sure the data is written to "'''/data/<telescope_name>/<instrument_name>/YYYY/MMDD/"'''.
==Unmounting SHOC==
** Check that the antenna cable has been connected to the SHOC GPS on the box.
** Check that the antenna has access to the sky (i.e. the dome is open)
** Check that the location settings are correct. Click on 'receiver status' in the GPS tab and look at the latitude and longitude. The Sutherland Latitude is ~32 22 S while Cape Town is 33 56S. If the location is not corrrectcorrect, then the GPS will not find satellites and the correct location needs to be updated as described in the Configuring SHOC section.
* Camera is in an inoperable state:
** Restart the services by sshing into the SHOC computer (see Configuring SHOC section):
