user manual

local/remote operation

  1. Turn off the pilot, which runs pt5m in robotic mode. The best way of doing this is to set the robotic flag to 1 by typing the command: /home/slodar/scripts/manual_mode. Robotic mode can be re-instated by typing /home/slodar/scripts/robotic_mode.
  2. Log in to ron (the PC in the lift-motor room which runs everything except the slodar CCD): ssh -Y Please ask a member of the pt5m team for the password. You can do this from any PC on the ING network, or via pulsar in Vik's office. If you want to observe in the dome, connect your laptop up to the switch on the trolley, look at /etc/hosts on ron and manually set your IP address to one of the IP numbers in this file that are labelled for use with laptops, e.g. Remember to disconnect the laptop wifi, select manual configuration of IPv4, and use for the subnet mask (leaving router blank).
  3. See what is powered on by typing: power status. Ensure the following are powered on: scope (Astelco cabinet), qsi (science CCD), video (video server to which the webcams and finder are attached), ota (optical tube assembly), humfispy (local humidity sensor, finder and internal [spy] webcam) and dehumid (dehumidifier). For example, if the qsi is off, power it on by typing: power on qsi (or power on 2). The light should be powered off when observing and the telescope should always be left powered on.
  4. Check the webcams by typing: firefox video &. To see more detail on a particular camera, click on the desired panel for a full-screen image. Note that viewing the webcams really slows down the link to ron. Use the webcams to ensure that no people or obstructions are visible inside or outside the dome.
  5. Check the weather by looking at the pt5m status page. You can check the various limits for pt5m by typing the command: limits. Do not open the dome if the humidity is >70% and/or the average wind speed is >10 m/s (36 km/h) and/or the temperature is <1 deg C. The dome will close automatically once these limits have been passed, and it will not allow it to be opened again until the humidity has fallen to 63%, the wind speed has dropped to 9 m/s and/or the temperature has increased to 2 dec C. If desperate, and you are sure it is safe to do so, It is possible to override these limits using the dome ignore-weather command, but this is only to be used if you are at the telescope.
  6. Check that the telescope daemon is running by typing: pps. If it is isn't running, start the telescope daemon by typing: tel start. It is recommended that you do this in a separate terminal. In the same terminal, initiate interactive control of the telescope by typing: tel i. If you don't do this, every telescope command must be preceded by tel, e.g. tel info. To quit interactive control, type: q
  7. It is also recommended that you open a separate terminal and issue the command: follow. This runs the tel info command once per second and returns the results in an easy-to-read format.
  8. A note on telescope power: The telescope mount is controlled by a 19-inch rack unit, hereafter referred to as the "cabinet". Mains power to the cabinet can be turned on and off using the command: power on scope. However, this should always be left on, and only powered off as a last resort. Just because the cabinet is powered on does not mean that the telescope mount is powered on. The latter is achieved via a tel poweron command, which is automatically performed whenever the telescope daemon is started. If the telescope daemon is already running, you can check the cabinet status by typing tel info, which will return one of the following values for cabinet power: -1 or 0 = off, 0.5 or 0.75 = standby, 1 = on. So a value of 0 would tell you that the cabinet power is off (and hence the telescope mount must also be off). A value of 0.5 would tell you that the cabinet power is on, but the telescope mount is off, in which case you will need to issue a tel poweron command. A value of 1 would tell you that both the cabinet and telescope mount are powered on. Note that whenever the telescope mount is powered on, whether automatically when the tel daemon is started or manually when a tel poweron command is typed, the telescope will datum both axes by moving approximately 20 degrees.
  9. Now that you have control of the telescope, it should be moved to a position that protects the primary mirror from falling debris (e.g. ice) when the dome is opened (or closed). To do this, first check the local sidereal time by typing: tel info
  10. Enter the coordinates of the telescope "dome opening/closing" position by typing, as separate commands on separate lines: tel ra [LST+4] 0 0 (e.g. if LST=10 30 20, then type tel ra 14 30 20) and tel dec + 20 0 0. Note the spaces around the "+". 
  11. The above command will not move the telescope. To do so, first determine whether or not the telescope is tracking by checking the value of the tracking parameter using the command: tel info. tracking=0 means NO, tracking=1 means YES on the East of the pier, and tracking=3 means YES on the West of the pier.
  12. If the telescope is tracking, typing the command tel load will set the telescope "dome opening" coordinates as the target position AND will slew the telescope.
  13. If the telescope isn't tracking, typing the command tel load will set the telescope "opening" coordinates as the target position but will NOT slew the telescope. The target position can be checked by typing tel info and inspecting the targ_ra and targ_dec parameters, allowing a few seconds delay for these parameters to be updated. Then, to slew the telescope to the target position, type: tel track
  14. If the telescope does not move, inspect the value of the (cabinet) status parameter by typing: tel info. If (cabinet) status=0, then all is ok, but if status=1, there is an error. To clear the error, type: tel clear. You may need to do this twice, and you may need to wait tens of seconds for the telescope to slew. If the telescope does not move after two attempts to clear the error, do NOT try it again: each clear command could move the telescope by 20 degrees as it attempts to datum, bringing it close to striking the floor. Please contact one of the pt5m team in this case, as a recovery procedure must be undertaken, which involves pressing the brake button on the mount and moving the telescope manually to approximately the park position.
  15. If all is well, the telescope should now be pointing towards the East, i.e. towards the top-left hand corner of the spy camera. The dome can now be safely opened without debris hitting the primary. Use pps to determine if the dome daemon is running. If it isn't, start it with the command: dome start. Then open the dome using the command: dome open. If it is windy, you can partially open the dome by typing, for example, dome open east 1 (where 1 is the number of "steps"). To open the entire east side of the dome, type dome open east 13. If the dome doesn't open, it may be because there has been a power cut. In this case, you will have to delete the file /home/slodar/config/EMERGENCY-SHUTDOWN, which prevents the dome from opening if present, and try again. (If you ever want to remotely perform an emergency shutdown, type touch /home/slodar/config/EMERGENCY-SHUTDOWN).
  16. Once the dome is open, check that the ota daemon is running using pps. If it isn't, start it with the command: ota start. Now open the primary mirror covers using the commandota shutter open.
  17. Start the qsi daemon by typing: qsi start. It is recommended you do this in a new terminal. The CCD will start to cool down to -20 degrees C - you can check the temperature by typing qsi temp. Note that the qsi queue (the status parameter) is paused on starting up the daemon, so you must remember to unpause the queue using the command qsi resume, otherwise you will not be able to take any data. If you have problems with the qsi exposure progress bar, e.g. if it causes the qsi daemon not to work, or if it scrolls down the screen in an annoying way, try turning it off by starting the daemon with the qsi start noprogress option. Or try running the qsi daemon in a vt100-compatible xterm (some unix consoles cause the qsi daemon to crash when plotting the progress bar), or try typing setenv TERM vt100 (If using tcsh or csh) or export TERM=vt100 (if using bash - to work out what shell you are using, type echo $SHELL).
  18. You are now ready to observe. Enter the RA and Dec of your target and then type tel load to slew to it. If you then need to tweak the position of the telescope, set the step size in degrees using, for example, the command: tel step 0.001 (for 0.001 degrees = 3.6"). You can then type tel n, e, s, w, which steps the telescope in these directions (so steps the star in the opposite direction on the CCD). Note that you must not type ahead - the system can't store the steps - and you must remember to clear these offsets when slewing to a new target using the command: tel centre. Also note that steps in the east and west directions are actually in RA units, so to step a given angle in arcseconds you must divide by cos(declination). To make life easier, you can use the /home/slodar/scripts/ script to calculate the steps for you.
  19. If you require flat fields, you can use the script /home/slodar/scripts/ to take them automatically, e.g. python /home/slodar/scripts/ EVE. Best run at sunset, the dome and mirror covers must be open, telescope tracking (although it doesn't matter where) and the qsi ccd cooled down. The script slews the telescope to a blank field and waits until the sky is at the correct brightness (approximately 25 kcounts). When at the right level, the script takes a series of flats in each filter, stepping the telescope to ensure any faint stars median out.
  20. Now set the focus. This can be done manually by moving the secondary mirror using the command ota foc 198.5, for example. Note that the focus value is given by the BFL parameter returned by ota info.The best focus value depends on the temperature and you can get a rough idea of the correct value by looking at the values used in previous observing logs. If you don't know the focus value you want to use, you can determine it automatically using the /home/slodar/scripts/ script. This requires only two parameters, the Half Flux Diameter (HFD, in pixels, recommended value=20) and the filter, e.g. autoFocus 20 V. The script slews to a suitable star near the zenith, determines the optimum exposure time, and then takes a series of images to determine the position of best focus. The script exploits the fact that that there is a linear relationship between the HFD and the telescope focus (when out of focus), and this relationship has been calibrated for pt5m. So if the actual HFD is measured at a particular telescope focus, it is straightforward to calculate the position of best focus. The script tweaks the focus until it reaches the user-defined target HFD (20). Once near this value, the actual HFD is measured and the best focus position is calculated. Note the autoFocus script will fail if not run from a vt100 compatible terminal. If using tcsh or csh, setenv TERM vt100, if bash export TERM=vt100 (to work out what shell you are using, type echo $SHELL).
  21. To view the autoFocus (or any) data, change to the current data directory (e.g. /home/slodar/data/qsi/2015-07-10) and type: autoplotter. This script opens a ds9 window and then polls the data directory looking for new data files. When one appears, it automatically plots it on the display, setting appropriate zoom and contrast levels, and showing the orientation of the chip on the zoom inset display. When tracking=1 (E of pier), N is right and E is down on ds9, and when tracking=3 (W of pier), N is left and E is up on ds9.
  22. If you need to observe a flux standard star, you can use the script /home/slodar/scripts/ to take them automatically. Best run in twilight on cloud-free nights, the script takes as input the colour and airmass of standards that you desire. For example, python /home/slodar/scripts/ -0.2,0.0,0.2 1.0,1.2,1.5 2 will slew to three Landolt standard stars nearest to the specified pairs of colours and airmasses (-0.2,1.0), (0.0,1.2), (0.2,1.5), take images at each position, and calculate the photometric zero points. The last parameter (2) is the binning factor required.
  23. You are now ready to slew to your first science target. Once there, type qsi to obtain a list of the various ccd control commands and the options that they take. (Similarly you can view all of the available dome, power, tel, qsi, and ota commands by typing, dome, power, tel, qsi, ota, respectively. Note that you can't do this when in interactive mode.) It is a good idea to use the qsi glance command when acquiring an object, as this does not write a permanent run file to disk and hence prevents filling up the archive with useless data. Only when the object has been properly acquired and the optimum exposure time determined should you use the qsi image (or equivalent) command, which will then write the data to a fits file of the form r0123456.fits.
  24. If you don't see any stars in the image, check the following: Is the dome open? Are the mirror covers open? Is the flipper mirror set to the CCD position? What filter am I using? Is my object below the artificial horizon? To check the latter, run the script artificial_horizon 268, for example, where 268 is the azimuth of your target.
  25. When observing your science target, keep an eye on the hour angle. When this gets close to zero, the mount will automatically stop tracking (i.e. tracking = 0). You will then have to wait until the target has passed into the western part of the sky before typing: track. The telescope will then automatically perform a pier flip, and resume tracking on the target. Note that the pier flip will cause the CCD orientation to rotate by 180 degrees, but this will be automatically displayed on the ds9 window thanks to the coordinate information written to the fits headers of each image.
  26. When observing is complete, slew the telescope to the "dome opening/closing" position described in item 10 above, close the primary mirror covers using the command ota shutter close, and then close the dome using the command dome close. If dark, you can double check the dome is closed by switching on the light or looking for stars on the finder.
  27. Now park the telescope to stop it tracking by typing: tel park. The telescope should now slew to close to the NCP. Type tel info to ensure that the telescope has stopped tracking. The telescope should be pointing towards the top right-hand corner of the webcam.
  28. Now power off the telescope mount by typing: tel poweroff. This prevents the high-pitched whining sound from occuring.
  29. It doesn't do any harm at all to leave the telescope daemon running, as doing so means that the status page remains up to date and one can check that the telescope is parked. Note that shutting down the telescope daemon does NOT automatically do a tel poweroff - the mount will remain powered on if you shut down the daemon without doing a tel poweroff first. (Note that the telescope daemon does, however, always do a tel poweron when it is started up). If you do wish to close the telescope daemon, type: tel shutdown. If the daemon has crashed or will not shut down cleanly, type: tel kill
  30. Remember that the telescope should never be powered off using the power off scope command. The only time this might be necessary is when the cabinet crashes. This happens approximately once per month. When it does happen, the telescope daemon will crash and repeatedly fail to start. Pinging the cabinet using the ping scope command will also fail to produce a response. In this case, it is best to adopt the following procedure: Type tel shutdown, wait a few seconds and then type tel kill (to make sure the telescope daemon has shut down). Now power off scope, wait a few seconds and then power on scope. Try ping scope until you get a response, which may take a few minutes, and then type tel start. You should note that you had to do this in the failure log: /home/slodar/failureLog.txt.
  31. Finally, if you're not going to take any dark or bias frames, stop the qsi daemon with the command: qsi shutdown. This will allow the CCD to warm up to ambient temperature - you won't be able to start the qsi daemon again until the CCD has warmed up to approximately +10 degrees C. There is no need to stop any of the other daemons.

robotic operation

For robotic operation of pt5m, all you need to know is how to enter an observation into the queue, how to monitor what is going on with the telescope and your observation, and how to retrieve your data. These three steps are described below:
  1. To enter an observation into the queue, you either need to use the queue entry form or a python script (available on request).
  2. You can monitor the queue by viewing the queue page
  3. Robotic mode is run by a python script called Use pps to determine if the pilot is running - if it isn't, it will be started automatically by cron at 17:00 each day.
  4. The pilot won't run if the robotic flag is set to 1. To set it to 0, type the command: /home/slodar/scripts/robotic_mode.
  5. If, for some reason, the pilot is not running and you wish to start it, you need to type python scripts/ Note that this will close the dome if it is already open, as one of the first things the pilot does is take bias frames with the dome closed. If you are restarting the pilot in the middle of the night and want to skip all of the start-of-the-night checks and procedures you should instead type python scripts/ restart - the restart option leaves the dome open and jumps straight to observing jobs from the queue. 
  6. Note that if you do run the pilot manually, it is best to do this in a screen session so that the pilot does not hang when you close your laptop. To do this, type screen in a terminal, then in the screen terminal type python scripts/ and then type ctrl-a-d to disconnect the screen session - you can now safely close your laptop. If you then want to resume the screen session, simply type screen -r.