Usage of the Schmidt telescope

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How to start observing

1. Switch on the electricity and the lights of the dome with the switches right at the entrance door.

2. Login to the control computer,, with your own account

3. Switch on the cooler of the camera. This can be done by using the energenie-manage command on the control computer. By simply typing this command, it tells whether the cooler (and the camera) is turned on or not. If it is off, use the command

$ energenie-manage --cooler on

to switch on the cooler. The cooler is noisy: if it is switched on, it can clearly be heard even inside the dome (if the telescope or dome is not moving).

4. If the above energenie-manage call says that the camera is also switched off, use the command

$ energenie-manage --camera on

to switch it on. Usually, the camera is on power, constantly, but it is worth to check the power status of the camera. After the observations, it is not necessary to switch it off.

5. Check whether the filter wheel is switched on (by default, it should always be switched on). If not, use the small switch to put it into the ``on state. After switching on, the display is going to be on red and the filter controller moves into home position. Following the successful initializing and homing, one should see a single ``E on the display of the filter controller.

6. Switch on the telescope. Wait until the oil pressure is appropriate (few tens of a second). Check also the three phases of the electric power (lights with R, S and T, on the control panel). Only these three light should be on, all of the others (oil pressure, etc.) should be off.

7. Remove the tube cover. Since the convenient position for removing the tube cover is beyond the software limitations, always use the telescope control panel to move the telescope in this position. Similarly, after removing the tube cover, move the telescope manually (i.e. still using the telescope control panel) to some reasonable horizontal altitude in order to allow the software backends to handle the telescope motions properly.

8. Check the subsystems by running the command schmidt-test. If everything is fine, you may see something like this. In general, the green [Ok] status means that the given part is ready for observation while the cyan [Info] means that the observer should perform some of the above routine turning-ons (see e.g. this example). In the case of an [Err!] state, then please consult with the appropriate personnel about the problem. Please note that slightly after turning on the CCD, it also reports this [Err!] (like this), but it should disappear after a few seconds.

9. Start the program ccdsh from a terminal of the control computer.

10. Check the status of the telescope and control subsystems by typing the command status to the ccdsh command prompt:

CCD> status
CCD:      ready # 0 idle 
Mount:    ready # 0 idle ura=210.9274 udec=54.2869 st=308.1185 utau=97.1912 mx=0,0,0
Dome:     ready # 0 tracking 0x0
Filter:   ready # 0 idle 
Focuser:  ready # 0 idle 
Logger:   ready # 0 idle 
Logger:   ready # 0 idle 
Resolver: ready # 0 idle 
Resolver: ready # 0 idle 
Command:  ready # 0 idle 

Check if all of the essential control subsystems (CCD, mount, dome, filter, focuser) as well as the other ones (loggers, especially) are available and have a status of ready (displayed in green). If the telescope is not switched on, you will see the status of the mount, dome and focuser as an error (displayed in red), usually with a message of -1 unreachable.

11. If the camera and filter wheel is not availabe (i.e. lines starting with CCD: or Filter: do not appear in the list above, yielded by the command status), use the command

CCD> source /usr/local/ccdsh/scripts/load-camfilt-apogee.ccdsh 

to load the essential modules. If this script runs successfully, re-check again the status of the control subsystems using the command status as above. Please use always the script located in the directory /usr/local/ccdsh/scripts. This script might be modified in the future, and it is not guantareed that a former version of this script works with an updated version of the control modules and/or the ccdsh program.

12. Start cooling the camera, by using the command

CCD> set temperature -35

In winter, you can cool down the camera to -40 degrees as well. In summer, cooling down to -40 degrees might yield instabilities. Use the command get temperature to check whether the camera has cooled down sufficiently. Note that this cooling is a slow procedure and might require even half an hour to be completed. However, you can start camera cooling independently from the telescope control. So, if you are sure about everything (esp. that the cooler is switched on), you can start the cooling earlier, remotely. The camera and telescope control subsystems are totally independent, so if the whole telescope is switched off, the camera is available (i.e. the CCD: is listed by the status command and it is ready, see above), the cooling can also be started.

13. Open the dome slit door. This might be done using the telescope control panel in the dome area or via ccdsh, involving the command set dome slit open. If this is used, use the command get dome slit to track the status and wait until the slit door is fully opened. If the dome is in home position, and there are some lights in the dome area (see the notes at the end), you can clearly see the slit door via the webcamera (see also the notes).

14. Start observing. The telescope can be slewed to any position using the slew command of ccdsh. Individual images can be taken using the acquire command (for testing purposes, for example). Complex series of images can be created via the command sequence. There are many commands in ccdsh that makes the observations convenient (object name resolves using databases such as Simbad or MPC, definitions of favourite and frequently observed objects, visibility calculations and visibility graphs, and so on). Here we refer the full documentation of CCDSH (in English). Please use the command status regularly, both after and before complex operations and/or long image sequences to check if every subsystem operates properly. Wait until the operations complete: if the status of some of the subsystems (e.g. mount, CCD or filter wheel) is busy (displayed in yellow), you might have to wait a littlebit until the operations are completed and the telescope system becomes ready to use.

How to finish observations

1. Make sure that the telescope subsystems completed their work. Never start shutting down the system before any of the controls is in a busy state.

2. Close the dome slit door (locally from the telescope control panel in the dome area or remotely, using the appropriate ccdsh command).

3. Switch off the camera cooling:

CCD> set temperature off

In summer, it is neccessary to completely switch of the camera cooling if the cooler does not circulate the coolant. In winter, however, one can set the CCD temperature to -10 ... -15 degrees without any instabilities even if the cooler is switched off.

4. You may want to move the dome to its home position. The normal home position of the dome is at azimuth=70 (the slit door looks west-southwest). It is not essential, but recommended. You can use the appropriate ccdsh commands as well: set dome auto off, followed by set dome azimuth=70 and then wait until the dome moves to its home position (see also the status command).

5. Exit from the ccdsh program.

6. Put on the tube cover.

7. Switch off the telescope.

8. Switch off the cooler of the camera. Use the command

$ energenie-manage --cooler off

from the control computer to switch it off.

9. Log out from the control computer as well.

10. Switch off the electricity and the lights of the dome.


  • The orders of the procedures in lists above are not so strict, so the observer may alter the order depending on the actual needs. For instance, ccdsh can be started before switching on the telescope. In this case, the status command will report errors for the mount, dome and focuser, but immediately if the telescope is switched on, the status messages also change to ready. Of course, there are obvious dependencies: one cannot switch on the telescope until the main electricity switches are off, or the tube cover cannot be removed (or, more precisely, the telescope cannot be slewed to this position) until the telescope is switched off and so on.
  • Never try to control the telescope movements simultaneously from the telescope control panel in the dome area and from the ccdsh software. If the mount and dome status is ready for both units and the dome status is idle (and not tracking) it is safe to control the telescope from the panel as well. But either the mount and dome are busy or the telescope is started to slew from the control panel, never try to use the another type of control. Note that this is true even if some kind of errors are encountered. If the telescope seems to be stuck or moved to some highly unexpected position, first check the status messages and report these. After, ensure that the controls are released from ccdsh, i.e. check the <codoe>status, and make all of the systems ready by saying set dome auto off, set mount stop and set dome stop. If both the dome and mount are ready, one can go to the control panel and solve the problem manually.
  • The observer can also use the ccdsh commands set dome light 0 on and set dome light 0 off to switch on and off the flat lights in the dome. The light 0 is the fainter one (that is used routinely for taking dome flats) and the light 1 is the brighter one. By switching on the latter one, the dome slit can be seen clearly if the dome is rotated to azimuth=70.
  • The state of the telescope, dome position, the image of the all-sky camera (including the marks of the telescope pointing) and the dome area web camera can be tracked real-time from this location: This web address is temporary, and might be changed in the future. If the brighter dome flat light is on (see above) and the dome is at the home position (azimuth=70), the slit door can clearly be seen via the web camera.
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