Preliminaries Filling the WFC cryostat Zeroset the encoders Opening up Switching TCS in computer mode Closing Down Switching TCS in engineering mode Filling cryostat - morning Writing Tapes Printing observing log Filling Logbook Preliminaries Switch off lights on all floors, close the blind in the restroom. In the control room, first check the Operations Logbook for any restrictions that may be still in force. Turn on the DOME LIGHTS from the console and raise the control room blind. Make a visual inspection of the observing floor (and the balcony above the control room if the telescope is at ACCESS PARK) to check that the telescope is free to move e.g. no ladders or steps are close to the telescope or test instruments connected. Put the Telescope in ENGINEERING MODE by pressing the ENG/COMP push button. The button should now be illuminated with an yellow light, indicating ENG mode has been selected. Clear any emergency overrides by pressing the RESET button close to the ENG/COMP button. Ensure that none of the SELECT MANUAL CONTROLS buttons have been activated on the console Make sure that the TCS/DAS/ICL software is running. If not, please follow this link before proceeding. Turn on OIL PUMP from the engineering rack. Filling the WFC cryostat Moving the telescope to ACCESS PARK To do this, on the engineering rack: Ensure the telescope is at ZENITH PARK and the HA synchro pointers are at the "12:00" position. Turn the DEC QM variable speed control fully clockwise. Push the DEC QM button to release the slow motion clamps. Push and hold the DEC [+] button. This will move the telescope down towards the balcony. At declination 100 degrees the HORIZON LIMIT alarm activates. The telescope will stop and the slow motion clamps will re-engage. Push the ACCEPT button to mute the alarm. In order to move to 106 degrees (position for filling the cryostat) turn and hold the LIMIT keyswitch clockwise in the OR (override) position whilst pushing the DEC QM button to release the slow motion clamps. Push the DEC [+] button until close to 105 degrees, the telescope will then stop at about 106 degrees. Filling Cryostat When the telescope is at ACCESS PARK, wheel the N2 dewar close to the platform. Connect the dewar to earth; use the earthing point on the hand rail to the right of the telescope. FULLY insert the filler tube into the cryostat. On the dewar, CLOSE the PRESSURE RELEASE valve. OPEN the DECANT valve. OPEN the PRESSURE AUTO valve. n.b. Check the pressure does not exceed 15 psi. If the dewar is low on liquid nitrogen, the PRESSURE MANUAL valve can be opened. Use precaution when doing this as the pressure can build up very quickly if the dewar is close to full. Wait until liquid nitrogen is SEEN to be coming out of the cryostat. CLOSE the DECANT valve and the PRESSURE valve(s). OPEN the PRESSURE RELEASE. Removing the filler tube with care. VERY IMPORTANT! Wear safety helmet (with visor) and gloves when filling cryostats! Always remember to leave the PRESSURE RELEASE valve on the dewar OPEN. If this is forgotten, pressure can build up over time and burst the relief valve on the dewar. This is especially true if the dewar is close to full. Moving the telescope out of ACCESS PARK To do this, on the engineering rack: Turn the DEC QM variable speed control fully clockwise. Turn and hold the LIMIT keyswitch clockwise in the OR (override) position whilst pushing the DEC QM button to release the slow motion clamps. When the clamps have disengaged, still holding the LIMIT keyswitch to OR, push the DEC [-] button. This will move the telescope up and away from the balcony. When declination is below 90 degrees you may release the keyswitch. If the audible alarm sounds, push the ACCEPT button to mute it. If the encoders have already been zeroset, push the DEC SM button and put the TCS into Computer Mode. Bring telescope to zenith by USER>park zen. If no zeroset has been done yet then, Continue to push the DEC [-] button until the telescope is vertical. The DEC synchro pointers should be close to the "9:45" position. When the telescope is vertical, push the DEC SM button to re-engage the slow motion clamps. Zeroset encoders Visually check that the telescope is near zenith park (i.e. vertical). The HA synchro position indicator pointers should be near the "12 O`Clock" position with the DEC indicator pointers near the "9:45" position. If the position indicators are some way off, move the telescope close to these positions using the HA and DEC [+]/[-] buttons on the engineering rack. Select quick motion (QM) if the telescope is a long way off position then go to slow motion (SM) to make the final adjustments. In the TCS User window, enter: USER>zeroset ha target (or: zero ha tar) USER>zeroset dec target (or: zero dec tar) Using the HA and DEC [+]/[-] buttons with slow motion (SM) selected and the drive rate controls adjusted for a very slow speed, move the telescope so that the synchro dial pointers MOVE THROUGH the "12 O' Clock" position in HA and the "9:45" position in DEC. The TCS will beep if the zeroset is successful. The yellow LED's mounted above the synchro dials will momentarily flash also confirming that the telescope has been zeroset. Opening up Opening the dome top shutter On the engineering rack: Use RAISE MICRO until the OVERTRAVEL indicator goes off. Push RAISE MAIN until the shutter stops moving. The shutter is now fully open. n.b. If the dome or shutter does NOT work from the engineering rack push buttons, go up to the balcony and check the manual controls on the large grey cabinet mounted on the dome. The switches (key operated) associated with the dome and shutters must all be pointing to REMOTE, not to LOCAL. To operate the lower shutter, follow these instructions. Push and hold the PRIMARY MIRROR OPEN button. Check the mirror petals open fully (petals can be seen moving through a gap in the telescope structure). Push the DOME VENT FAN button to enable dome ventilation. The red light will go OFF when the ventilator is on. Turn off the DOME LIGHTS from the console and close the control room blind. Switching TCS in computer mode Put the telescope into Computer Mode by turning the COMP keyswitch. The green section of the ENG/COMP push button switch should illuminate showing that Computer Mode has been selected. n.b. The HA and DEC slow motion (SM) push buttons MUST be set for SM mode (i.e. All the lower green sections of the buttons illuminated) before Computer Mode can be selected. If the yellow section of a QM button is illuminated, push the adjacent SM button to re-engage the slow motion clamps. Computer Mode should now be available. TELESCOPE IS READY FOR OBSERVATIONS Closing down Bring the Telescope to zenith by typing USER> park zen Push and hold the PRIMARY MIRROR CLOSE button. Check the mirror petals close fully (petals can be seen moving through a gap in the telescope structure). Push the DOME VENT FAN STOP button to turn off dome ventilation. The red light will go on when ventilator is stopped. Closing the dome top shutter Always remember to bring down the lower shutter first On SELECT MANUAL CONTROLS activate the button labeled dome/shutter. On the engineering rack: Push LOWER MICRO until the MAIN OVER TRAVEL light goes off. Use LOWER MAIN until the shutter stops moving. Push LOWER MICRO to fully close the shutter. Release the button labeled dome/shutter on SELECT MANUAL CONTROLS. n.b. There are a few rules concerning dome shutter and bad weather. When windy and raining from behind the shutter water can penetrate into the dome; there is a seal but it isn't perfect. Therefore in this case please turn the dome to point the shutter into the wind. On the other hand with temperatures below zero we would like to avoid the build up of ice on the shutter, in this case point the shutter out of the wind. Switching TCS in engineering mode Put the Telescope in ENGINEERING MODE by pressing the ENG/COMP push button. The button should now be illuminated with an yellow light, indicating ENG mode has been selected. If an audial alarm sounds, type USER>ack to mute the alarm. Filling cryostat - morning As at the start of the night, the WFC cryostat needs to be filled: Bring the Telescope to Access Park. Fill the Cryostat. These procedures are described here. Turn off OIL PUMP from the engineering rack. Writing tapes There is a possibility that torn images are related to the writing of tapes while doing exposures (and the consequent reading of the chips). For this reason the following advice: Please do not write tapes while doing observations; start writing them in the morning when observations are finished. Check whether the drives need cleaning, this is the case if a LED is flashing every 4 seconds. The cleaning cartridge is placed together with the empty tapes together with instructions on how to use it. Insert the DDS3 (125m) tape in the drive /dev/rmt/0n or /dev/rmt/1n Logon to lpss8 as intguest and change directory to the data directory /obsdata/... lpss8>fitsinit - follow the displayed instructions on how to initialize the tape. lpss8>fitsout - again follow the instructions on the screen. On a DDS3 tape (12GB) should be enough space for 150 runs. Note that a list of missing runs will appear on the screen which you have to acknowledge before the writing process begins. Printing observing log Fill in the observing log html form, select how many printed copies you need and submit. Please archive one copy of the observing log in our log folder. URL: http://scorpio.roque.ing.iac.es:9999/intlogentry.html Filling logbook The printed logbook in the control room contains fields which must be filled out during the night: CCD cryostats : Initials and local time for filling the CCD(s). Breakdown of observing time: Fill in any downtime that was encountered (bad weather, technical problems, etc.) and note the time lost.

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