Last modified on 23 October 2019, at 18:34

Lesedi

Revision as of 18:34, 23 October 2019 by Hannah (Talk | contribs) (The Observing Floor)

The "new" 1-m telescope was installed in the dome that previously housed a 30-inch telescope. The telescope was built by APM Telescopes[1] and was lifted into the dome on 02 August 2016. Commissioning is currently underway.

The 30-inch telescope was donated to the University of Kwa-Zulu Natal.

Watch this space!


Contact numbers

To receive calls, the phones in the warm room and on the observing floor can be reached by the following numbers:

Extension number: 9109 (to phone from within the observatory)


To make calls if you have a problem that isn't addressed in this wiki or the fault forum (remember to dial the ** where given):

1.9m/74-inch observer: 9107

1.0m/40-inch observer: 9108

Cape Town remote observing station: 7027

Standby electronics technician: **103

Standby mechanical technician: **104

Standby IT technician: **113

A guided tour of the dome

The purpose of this section is to introduce you to the facilities and equipment you will need during your run. The tour begins at the front door of Lesedi's dome. To aid orientation, the domes of MeerLICHT, Lesedi, and the 40 inch are aligned East-West, perpendicular to the main road that passes SALT at the Northern end of the plateau and leads to the "Robotic Row" of telescopes in the South. A code (which you can obtain from the standby technicians/your support astronomer/other observers) is required to open the door.

Main lighting circuit switch

Just inside the entrance on the left-hand wall is a master switch to control all the lighting circuits in the building. Switch it on if you are working in the building, and always ensure that it is switched off when you leave, especially if people are observing remotely.

Light switches

  • Foyer and stairwell light switches can be found on the right-hand wall, just around the corner to the right, at the foot of the stairs (foyer light switch on the right, stair lights on the left). There is a second switch for the stairwell lights at the top of the stairs.
  • Light switches on the left at the top of the stairs. The left-hand switch is for the stairwell lights; the other for the observing floor incandescents.
  • The switch for observing floor fluorescent lights is located up the ladder on the observing floor, on the dome control console mounted on wall above the North end of the pier.
  • The slew lights on the ring beam are software controlled.

Ground floor facilities

As you enter the dome on the ground floor, you will find the following facilities:

  • Fire extinguisher: mounted on the wall as you enter.
  • First aid kit: on a shelf to the right as you enter the dome.
  • Toilet: through the first door on the left as you enter the dome. The light switch is outside the door on the right. The right-hand switch operates an extractor fan(!).
  • Kitchen:, second door on the left. It has a microwave, coffee maker, kettle, toaster, snackwich and an array of cutlery and crockery in the cupboard under the sink. There are jars of teas, coffees, hot chocolate and sugar. If these jars become empty, return them to the hostel kitchen in your night lunch bag for refilling. The kitchenware is cleaned daily by the hostel staff, except at weekends.

The warm room

The warm room is the door on the right-hand side, opposite the kitchen. It contains an air-conditioned server room and has the following resources at your disposal:

  • A PC ("lesedi-nuc") for running the telescope and instrument control systems.
  • Several network cables and power sockets for use with laptops.
  • Lights on a dimmer switch (push and hold to adjust the brightness) and a desk lamp.
  • An air conditioner to heat or cool the room.
  • A stereo compatible with iPods and iPhones, and plays CDs, MP3s from DVDs and USB devices, and has a radio.

The Observing Floor

At the top of the stairs, be careful not to trip over the raised hatch in the floor (this is for lowering the primary mirror for aluminising). You will find Lesedi on a raised pier, surrounded by a metal grid floor, accessed by a ladder. The North end of the pier is nearest the stairs. Familiarise yourself with the following:

  • Dome control console at the North end of the pier.
  • Dome lockout switch beside the dome control console at the North end of the pier. Note that this does not lock out the telescope, only the dome. Lockout should be switched on (a red light on the box will flash) if people are working on the dome, otherwise left off.

The Telescope

Lesedi is a 1-metre Alt-Az Ritchey-Chretien telescope. There are two Nasmyth foci, each with an instrument rotator and identical corrector optics. The Nasmyth ports are identified as left and right, defined from the point of view of someone standing behind the parked telescope, i.e. looking at the back of the primary mirror cell. SHOC is mounted on the right-hand port, and Sibonise will be commissioned on the left in the near future. Future instruments (a low-resolution spectrograph and a fibre-fed echelle) will be co-mounted on an instrument selector to share the right-hand port with SHOC. A motorised tertiary mirror allows an instrument on either port to be selected in seconds.

The telescope is parked facing East, the dome to the West. There shouldn't be any need for manual interaction with the telescope during the night, but you should ensure that the observing floor is clear of ladders and other obstacles before moving the telescope, and that the mirror covers are closed before opening the dome.

Commissioning Aids

Centre of rotation on SHOC

19 Jan 2017: (527,538) - SHOC removed to check mounting (all ok) & countersink ND filter wheel screw below camera mount plate

18 Jan 2017: (530,527) - secondary retaining ring & radial screws tightened

7 Nov 2016: (524, 527) - primary & secondary mirror retaining screws & secondary retaining ring tightened


Latest model (model_38s) based on 18 Jan pixel coordinates

Start-up recipe

  • Log into SHOC as shoc1m at http://shoc1m.suth.saao.ac.za:5000 and switch camera on
  • If in the dome, log into the NUC as ccd
  • Open a terminal and ssh -X observer@1ms1.suth.saao.ac.za
  • rts2-mon
  • In CUP menu, check that manual=false. If not, manually switch off dome lockout on observing floor
  • centrald -> "on" to open dome, followed by baffle and mirror covers

Shutdown recipe

  • centrald -> "off" to close mirror and baffle covers, park telescope, park and close dome
  • (These steps can be done individually with: APM0 -> "close", T0 -> "park", CUP -> "close", CUP -> "park")
  • (The close commands can be done in one combination: centrald -> "close" to close mirror covers, baffle cover, then dome)
  • Switch on lights (CUP -> toggle "lights" parameter) to check telescope & dome via webcam: http://10.2.50.12/control/userimage.html then switch lights off

Running SHOC through rts2

  • Start rts2 control of SHOC on shocndisbelief:

ssh ccd@shocndisbelief.suth.saao.ac.za
sudo bash
cd /home/petr/rts2/src/camd
sudo killall CameraServer && sudo ./rts2-camd-andor --server 1ms1.suth.saao.ac.za

  • Take images with SHOC:

ssh -X observer@1ms1.suth.saao.ac.za
rts2-xfocusc -d C0 -e 1
(where -e is the exposure time option. Add "-X 1" to overlay grid lines).

  • Take and save an image with SHOC:

CTRL-C out of rts2-xfocusc
rts2-scriptexec -d C0 -s 'ADCMODE=15 E 1'

Running SHOC from web browser after running it through rts2

  • This won't work without first rebooting shocndisbelief:

ssh ccd@shocndisbelief.suth.saao.ac.za
sudo reboot -h now

Need to then restart data spooling to the server:
(1) copy the temporary files that were written to /data/spool on the spindle drive to the SSD. Procedure:
mount /dev/sdb1 /mnt
rsync -avz /data/spool/* /mnt/

(2) umount the SSD from the /mnt mount point
umount /mnt
(3) Mount the SDD on /data/spool
mount /dev/sdb1 /data/spool

(4) Check it's mounted
df -h

See https://itwiki.saao.ac.za/index.php/Standard_Nagios_Notifications for more info.

Running AG Lodestars through rts2

  • Check whether Lodestar is connected:

ssh pi@1mag1.suth.saao.ac.za (or pimag2 for DER2)
lsusb
Look for "Starlight Xpress Lodestar autoguider" in output

  • Start rts2 control of Lodestar on the pi:

ssh pi@1mag1.suth.saao.ac.za
sudo bash
/etc/init.d/rts2 start

  • Take images with the Lodestar:

ssh -X observer@1ms1.suth.saao.ac.za
rts2-xfocusc -d AG1CCD -e 1
(where AG1CCD is on DER1 and -e is the exposure time option).

  • Take and save an image with the Lodestar:

CTRL-C out of rts2-xfocusc
rts2-scriptexec -d AG1CCD -s 'E 1'

  • Loop multiple saved images:

rts2-scriptexec -d AG1CCD -s 'for 5 {E 1}'
(also rts2-xfocusc --save)


Pointing tests

Follow section on Running SHOC through rts2 then

Run the model:

run_model_random3

Build the model:

gpoint --refine /etc/rts2/T0_model --filter 'model-err:15' align -o ~/model_XXs 
cd /home/observer
sudo cp model_XXs /etc/rts2
sudo rm /etc/rts2/T0_model
sudo ln -s /etc/rts2/model_37s /etc/rts2/T0_model
sudo rts2-stop T0
sudo rts2-start T0

Troubleshooting

  • Telescope does not respond to move or altaz command:

In T0 menu, check auto_mode_az=on and auto_mode_alt=on

  • Naughty telescope claims "Trying to contact centrald" and rts2-mon won't start:
sudo /etc/init.d/rts2 start
  • Certain subsystems don't wake up:
sudo /etc/rts2/start-rts2
  • Certain subsystems don't wake up with start-rts2 command above:
ps -Af | grep rts2
sudo killall <relevant process>

where <relevant process> could be: rts2-centrald - comms (?)
rts2-apm-multidev - mirror & baffle cover & primary mirror fans
rts2-teld-sitech-altaz - alt & az motors
rts2-sitech-focmirror - M2 and M3
rts2-rotad-sitech
rts2-httpd - for thrift?
rts2-cupola-saao - dome

Then restart:

sudo rts2-start <relevant process>

e.g. rts2-start CUP

Names of devices can be found in /etc/rts2/devices

  • Derotators still don't wake up with start-rts2 command above:
sudo rts2-rotad-sitech -f /dev/derotators --defaults-der1 =/etc/rts2/D1.ini --defaults-der2 =/etc/rts2/D2.ini 


  • Initialisation files for each subsystem are stored in /etc/rts2