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/* Filters */
== Current status and issues ==
Things to be aware of at the present time (updated April 2022):
# The wind blind is currently out of commission, pending repairs to a cable.
# Information regarding the filters installed in the instrument can be found [[#Filters|below]].
== Where to find the information you need ==
This wiki is intended to supplement the existing TCS and instrument user's guides, filling the void of information about the telescope and facility, and providing recipes for observing with the telescope-instrument-TCS combination.
For detailed information about the TCS and instrument softwareinstruments, please refer to the manuals listed below, which are available in the warm room, the hostel library, and are linked to on the 1.0-metre section of the following web page: http://www.saao.ac.za/observing/operating-manuals * "1.0-m Telescope Control Software: A User's Guide" by Stephen Potter & Hannah Worters * [https://www.saao.ac.za/wp-content/uploads/sites/5/SAAOCCDmanual.pdf "SAAO CCD Camera Control Program, version 1.2" by J. W. Menzies] * [https://shoc.saao.ac.za/Documents/ShocnHelpful.pdf "SHOC User Guide", by Rocco Coppejans] – contains useful instrument info, but new software described on SHOC wiki
* [https://topswiki.saao.ac.za/index.php/SHOC SHOC wiki]
* [https://shoc.saao.ac.za/Documents/ShocnHelpful.pdf "SHOC User Guide (SHOCnHelpful)", by Rocco Coppejans] – contains useful instrument info, but new software described on SHOC wiki
* [https://shoc.saao.ac.za/SHOCsnr.html SHOC exposure time and prebin calculator]
* [https://shoc.saao.ac.za/Pipeline/README.txt SHOC data reduction pipeline]
* [https://cloudcape.saao.ac.za/index.php/s/9QgG2QpI3GSnoO8"SAAO CCD Camera Control Program, version 1.2" by J. W. Menzies]
Much of this page assumes that the user has never before set foot in the dome, and has no local human to guide them. [[40" / 1.0m#Telescope pointing limits|Telescope pointing limits]], [[40" / 1.0m#Troubleshooting| troubleshooting information]] and [[40" / 1.0m#Start-up recipes|start-up]] and [[40" / 1.0m#Shutdown procedures|shutdown]] recipes should prove useful for experienced observers and novice users alike.
=== Contact numbers ===
'''To receive calls''', the phone in the warm room can be reached by the following numbers:
Extension number: 9108 (to phone from within the observatory)
To phone the dome from outside: 023 100 0222 (+27 23 100 0222 from outside South Africa)
'''To make calls''' if you have a problem that isn't addressed in this wiki or the [https://faultreports.saao.ac.za/index.php?board=4.0 fault forum] (remember to dial the ** where given):
1.9m/74-inch observer: 9107 (often a good place to start, given that the TCS and SHOC interfaces are common to both telescopes)
Standby electronics technician: **103
Standby mechanical technician: **104
Standby IT technician: **113
Extension number: 9108 (to phone from within the observatory)
To phone the dome from outside: 023 100 0222 (+27 23 100 0222 from outside South Africa)
== 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 the 1-m 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 telescope power switch ===
Just inside the entrance on the right-hand wall is the main telescope power key switch. It should always be set to PLC for the telescope to be used. If it is not, [[#Contact numbers|call a technician]].
=== Light switches ===
In the warm room, you will find:
* '''For STE3 or STE4''', a monitor at the leftright-hand end of the desk labelled '''imag40''', running the CCD Camera Control software.
* A thin client with monitor labelled '''ltsp''' that saves the data from the instrument PC and can be used to run a web browser, ds9, etc. '''For SHOC''', it can be used to run the instrument control software via a web browser. It is possible to download your data to a laptop on the network from this PC (use '''scp''' or '''sftp ccd40@ltsp.suth''' - the monitor is labelled with the password).
* A PC running the '''Telescope Control Software (TCS)''' for acquisition and guiding. Associated with this is a second monitor which displays the target and telescope coordinates, etc.
* A black & white printer. Print command: '''lpr -Ppr40in ''filename'''''
===== Log books, etc. =====
* '''Users' guides''' for the TCS, STE3/STE4, SHOC and the retired UCT CCD, which contains useful information about the online reductions programme for STE3/4.
* A triplicate '''CCD Camera log book''' in which to record details of each image if you are using STE3/STE4. If you finish a log book, there are more on top of the metal cupboard on the observing floor. Please take the next book in numerical order. There is no such log for use with SHOC; you are advised to keep your own records, e.g. in a spreadsheet.
* A catalogue of photometric '''standard stars'''.
* An A4 sheet entitled '''Sutherland Observing Record''', on which to log the duration of observations, time lost, etc. each night.
===== General warm room resources =====
# A '''stereo''' compatible with iPods and iPhones, and plays CDs, MP3s from DVDs and USB devices, and has a radio.
# Assorted desk '''lamps'''.
* '''Blue console on the East side of the North pier.'''
* '''Grey box by the blue console.''' If the telescope reaches its safe operating limits, the red light on this box will flash, an alarm will sound and the telescope drives and dome rotation will be disabled. There is an override key attached to the box, used to allow the telescope to be moved out of the [[#Telescope pointing limits|limits]].
* '''Emergency stop button on the grey box.''' There is a large red button to press if the drive motors fail to stop. If you have reason to press this, [[#Contact numbers|call a technician ]] to investigate.
* '''XY-slide reset button on the grey box.''' On the top of the grey box with the emergency stop button is a small blue button to press if the TCS XY-slides fail to respond.
* '''PC monitor to the right of the North pier.''' This screen displays pointing information, including your target coordinates and current telescope coordinates, for use when slewing the telescope manually.
* '''Observing Floor Control Panel.''' On the North wall by the North pier there is a grey box labelled "Dome Shutter and Windblind Control", which has red buttons for opening/closing the dome shutter and raising/lowering the windblind. One must first switchon the telescope power (blue console) and press the top button labelled "Request Local Control" to activate the panel. The redindicator will illuminate when the panel is active. To open/close the dome, push and hold the appropriate button until the shutters stop moving and you hear a beep. To raise/lower the windblind, push and hold the appropriate button until the blind reaches the desired height. '''Do not raise the windblind while pointing into the wind; first rotate the dome by 180°, raise the blind then rotate back. '''There is also a switch for the upper dome lights.* '''Dome flat lamp switch.''' On the North wall, just above and left of the monitor, is a dimmer switch that controls the incandescent lamp used for taking [[#Dome flats|dome flats]].
* A red '''balance weight''' on a rope, which can be hung from an appropriate place below the primary mirror cell if the telescope jumps while tracking (usually when tracking around the zenith).
* Tall and short '''wheeled ladders''' for hanging the weight and for accessing the reset buttons on the Merlin transputer crates. Make sure the ladders are clear of the telescope while observing (the taller ladder is usually stored on the West side of the observing floor under the catwalk, the other is pushed to the East side of the North pier).
*'''STE3/STE4''' has its own blue '''instrument Merlin crate''' mounted to the cylindrical dewar. There is a red reset button on the side of the crate that should be pressed if the instrument control software hangs, crashes or reports a "Merlin error". There is no need for observers to fill the dewar with liquid nitrogen; this is done by technicians in the morning and afternoon.
* '''SHOC''' does not require liquid nitrogen; it is peltier-cooled. It has no Merlin crate. The control PC ("shocnawe" or "shocndisbelief" ) is mounted in a crate below the primary mirror cell.
=== Filters ===
The blue metallic box below the acquisition/guider box contains the filter wheel(s), labelled on the East and West sides. Each wheel has 8 filter positions; position 1 is the reference and position 8 is always empty, so that with two wheels installed, one wheel should always have position 8 in the beam (unless one wheel contains neutral density filters). '''Filters must not be removed from the filter wheels.'''
=== The old warm room ===
The old warm room is situated on the East side of the observing floor. The light switch is a dial just inside the main door on the right as you enter. The switch for the observing floor fluorescent lights is just inside the hobbit door to this room at the top of the stairs.
== Observing Limits limits ==
=== Meteorological constraints ===
The dome must be closed when any of the following weather limits is reached:
* '''Humidity''': T<sub>external</sub> - T<sub>dew</sub> ≤ 1.5
* '''Wind speed''': 60 km/h. Dome must be parked '''facing into the wind'''.
* '''Heavy cloud'''
The following should be used for regular monitoring of external conditions while observing:
* DIMM seeing data and all the weather stations on the plateau are summarised on this page [[http://suthweather.saao.ac.za/]this page]
* For assessing sky conditions, SALT and LCO operate '''all sky cameras''', also available on the website above.
The operational limits of the telescope are depicted in the figure below.
If the telescope reaches the limits, the drive motors will cut out, dome rotation will be disabled, an alarm will sound and a red light will flash on the grey box on the East side of the North pier. To [[#Contact numbers|Call a technician]] to recover, turn the override key on the grey box, switch the drives to FAST mode and slew the telescope away from the limits. '''Be very sure that you know which way to slew, as the telescope can be moved in any direction when the override key is turned.''' If in doubt, call a technician.
[[File:limits.png|1200px|frameless]]
3. '''Switch off the [[#Light switches|lights]]''' everywhere except in the warm room.
4. Check that '''Telescope Power Control''' (on the wall just inside the front door) is set to '''PLC'''. If not, [[#Contact numbers|call a technician]].
If observing in Sutherland: in the warm room, '''on the wall-mounted mimic panel''' at the left-hand end of the desk ('''if observing remotely, these things will be done by the on-site technicians'''):
10. '''Open the mirror covers''' by clicking the "DOME" pulldown menu and selecting "Mirror OPEN". The mirror indicator on the top right will turn green.
11. Switch '''dome to AUTO''' by clicking the red "MAN" button (top right of display). It will turn green. At times, it is necessary to either rotate the dome or point the telescope to Zenith so that the dome is able to locate its poisition and avoid the possibility of the dome not correctly following the telescope .
12. Turn '''telescope tracking on''' by clicking the red "Tracking is OFF" button. It will turn green.
=== If the TCS PC is switched off or not responding ===
Please [[#Contact numbers|call the duty electronics technician using ]]. === If the phone number displayed in TCS-web interface is not responding === If the warm roomTCS-web is not responding to any inputs, then make sure that the WebUser has Control button is clicked and shows green. To access the TCS from the web browser, click here [http://remoteops1desk.suth.saao.ac.za:5001/ TCS-Web]. [[File:WebUser-Control.jpeg|600px|frameless]]
== Instrument start-up procedure ==
=== STE3/STE4 ===
1. Follow the start-up procedure described in Sections 1 and 2 of the [https://wwwcloudcape.saao.ac.za/wp-contentindex.php/uploadss/sites/5/SAAOCCDmanual.pdf9QgG2QpI3GSnoO8|SAAO CCD Camera Control Program, version 1.2", by J. W. Menzies].
'''Important:''' Ensure that the following are correct in the blue "Details of Run" startup panel:
(Note: The data is initially written to the local disk on imag40 (/data/ccd/image/annnxxxx.fits). An rsync job runs on suthastro every 15 seconds which moves the data onto the SAN. This is accessible from the thin client, logged in as ccd40 in /data/40in/imag40/YYYY/MMDD.
=== SHOC === Follow the instructions on the [https://topswiki.saao.ac.za/index.php/SHOC SHOC wiki]. == Observing recipes: sky flats & dome flats ==
=== Sky flats ===
If sky conditions are photometric during morning/evening twilight, you will be able to take sky flats. See Section~\ref{sec-domeflats} if you need dome flats. Sky flats can be obtained in the following way:
# Follow [[#Start-up recipe|facility start-up procedure]].
# Follow the appropriate [[#Instrument start-up procedure|instrument setup procedure]].
# On the TCS, move the '''guide mirror out of beam'''.
# On the instrument PC, '''select the required filter'''. If you need flats in a variety of filters, be sure to cycle through them in the correct order (e.g. UBVRI during evening twilight; IRVBU in the morning). This also applies if you need a range of prebin settings (i.e. start with low binning in the evening; high to low binning in the morning).
# '''With STE3/STE4''', click "Expose", create a module, select "Flat" for the image type, and "Sky" from the pulldown menu beside it. Keep the count rates between 20000 and 50000. Remember to select "Yes" under "Save to Disk". Snapshots can be used to gauge integration times and can be saved to disk if appropriate. ''Section~\ref{sec-SAAOskyflats} gives Below is a [[#Sky flat recipe for STE3/4: Modules |recipe for taking sky flats]].'' See Section 4 of [https://www.saao.ac.za/wp-content/uploads/sites/5/SAAOCCDmanual.pdf "SAAO CCD Camera Control Program, version 1.2" by J. W. Menzies] for more detailed instructions on setting up a module.
# Take a '''minimum of 15 flats in each filter/prebin setting''', keeping exposure times ≥1s with STE3/4 to allow the shutter time to open and close (SHOC has no shutter so does not have this limitation).
Since all exposures with the STE3/4 must be performed via a module (except for snapshots), it may seem challenging to set up and edit modules quickly enough to obtain sufficient sky flats during twilight. However, you can do this pretty quickly using the following example:
# '''Before twilight''', set up a module for your first filter and an exposure time of 1s (do not go below 1~s1s), with 1 repeat.# For evening twilight, perform [[#Start-up recipe|steps 1-10 11 of the start-up recipe]] to setup the telescope and facility prior to sunset.# Click the small grey "On" button below the SAAO CCD image display.
# Shortly before (morning) or after (evening) sunrise/set ~10 minutes after sunset for B) click "Snapshot" → Exposure time = 1s. Click "Ready" to expose.
# Hover the cursor over the top portion of the image display as the image reads out, and read off the count level in the yellow "ADU" box below the image. Assess how the exposure time needs adjusting to maintain counts of 20000-50000 as the sky darkens/brightens.
With practice, you will easily be able to do this before the CCD finishes reading out in 2x2 binning.
== Observing recipes: on sky ==
=== Determining pointing offsets using a bright star ===
If you have trouble finding your target -- and you have checked the equinox and coordinates have been entered correctly into the TCS -- the problem may be the pointing. An offset can be determined for that part of the sky using the following procedure: #Follow the facility [[#Start-up recipe|start-up procedure]].
# Using the Astronomical Almanac or Sutherland Almanac, select a bright star (~4th mag) near your science target (ideally within RA~30m and dec~10°).
# Check that the target and bright star selected are within the [[#Telescope pointing limits|observing limits]].
# '''Initialise''' the XY-slides.
# Move the '''guide mirror into the beam'''.
# Type the '''equinox''' of the bright star coordinates into the "SET EQUINOX" box and press "ENTER" on the keyboard.
# Set "Exp Time" to ~1s and "WINDOW" to "Full frame" to take images with the acquisition camera.
# Use the hand paddle arrow buttons in the lower left of the TCS display for fine adjustment of the telescope to the star's coordinates, while watching the image display for to centre the bright star to appear.# If the bright star is not apparentdoesn't appear, first check the equinox and coordinates are correct, then adjust "Exp Time" to ~10s and look for light from the star beaming in from one side of the image, revealing its position. Looking through the finderscope might help determine in which direction to move the telescope. If this fails, reduce the exposure time and scan the field systematically in RA & Dec.# Once the bright star appears, select the minimum exposure time, centre the star on the image and click "P" by the target Target button.
# Select "ZERO POINTS" → "Enter RA & Dec of Star", then type the '''catalogue coordinates''' of the bright star into the boxes and press "SET".
# The RA & Dec zeropoints will be displayed in the message box. Note them down with the HA \& Dec as you will need to re-enter them using "ZERO POINTS" → "Enter Zeros Directly" if the TCS software is restarted, or if you return to this part of the sky after using different zeropoints in a different position. You do not need different zeropoints for different equinoxes. There is no need to note the collimation coefficient as it is ignored by the pointing model.
=== Acquiring a target ===
# Follow the facility [[#Start-up recipe|start-up procedure]].
# '''Initialise''' the XY-slides.
# Move the '''guide mirror into the beam'''.
# Type the '''equinox''' of the target coordinates into the "SET EQUINOX" box and press "ENTER" on the keyboard.
# Set "Exp Time" to ~2-4s and "WINDOW" to "Full frame" to take images with the acquisition camera.
# Use the hand paddle arrow buttons in the bottom left of the display for fine adjustment of the telescope to the target's coordinates while watching the image display for to centre the target field to appear. Comparison with an 8x8 arcmin finderchart is most helpful.
# The position should be accurate if you have followed [[#Determining pointing offsets using a bright star|this procedure]], so check your zeropoints. If not, adjust "Exp Time" to search for patterns in fainter stars to compare with your finderchart. If this fails, then reduce the exposure time and scan the field by systematically adjusting RA & Dec.
# Once the target is identified, move the guide mirror out of beam and position it on the image display such that it falls target on the centre of the science CCD(STE3/4 or SHOC).
* '''For STE4''', position the star approximately on coordinates (210, 270) of the TCS image display, to coincide with the centre of the science detector (for '''STE3''', approximately (180,190)).
'''On the instrument PC:'''
* Take a snapshot (STE3/4) or preview (SHOC) to check the positioning of the target on the detector and adjust using the handsetarrow buttons on the TCS.
* Using '''STE3/4''', video mode can be invoked by clicking "Snapshot", entering an integration time, selecting "Video" and clicking "Ready". It can be stopped by clicking "Snapshot" and "Stop". Video mode automatically prebins the CCD, so remember to change back to 1x1 afterwards, if appropriate.
'''or'''
* '''For a long run or for exposures ≥100s, you should locate a guide star and setup set up the autoguider before integrating on your target.
=== Finding a guide star & autoguiding ===
'''At the end of an observation:'''
* In "XY Slides Control", click "STOP" to cease A/G camera integrations.
* In "XY Slides Control", click "Initialize" to home the XY slides.
== Shutdown procedures ==
10. Switch '''Telescope Power OFF''' using red power button
If observing in Sutherland (if working remotely this will be done by on-site technicians): , '''on wall-mounted mimic panel:'''
11. Turn '''Lockout ON''' (turn switch clockwise)
12. Check that '''SMD''' is '''off'''
'''On instrument PC:'''
== STE3/STE4: CCD Camera log book ==
If using STE3 or STE4, please fill in the triplicate CCD Camera log book for each image obtained, pressing hard enough for your words to register on all three sheets. If you are using SHOC, there is no such logso you should note all the relevant information in e.g. a spreadsheet for your records.
The fields are explained as follows:
If you encounter telescope pointing problems, check the time and date displayed on the TCS, as the cause could be the time server. If the date/time is wrong, please call the electronics technician for assistance.
Login to the Foscam app with the following details:
'''Email:''' it@saao.ac.za
'''PW:''' Ask IT
[https://itunes.apple.com/za/app/foscam/id924381688?mt=8 App Store]
'''URL:''' https://40incam.suth.saao.ac.za <-- This only works from Internet Explorer
'''Username:''' adminoperator
'''PW:''' Ask IT40incam
