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 to check that the telescope
is free to move e.g. no ladders or steps are close to the telescope or
test instruments connected. Locate the cass plug usually left on the
observing floor (black circular plate with a handle). If it is nowhere
to be found, chances are that it is on the telescope. In that case call
the Duty Engineer to have it removed.
- 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 CRYOSTATS
- Wheel the N2 dewar close to the rotator.
- Connect the dewar to earth using the next earthing point on the rotator.
- FULLY insert the filler tube into the cryostat.
- On the dewar, CLOSE the VENT 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 VENT valve. Remove the filler tube with care.
- Disconnect the earth cable and place the N2 dewar close to the wall.
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.
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 "9:50"
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 "9:50" 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.
SWITCHING TV SYSTEM ON
- Ensure the gain is turned all the way down. Switch on power to the TV
amplifier (black knot).
- Turn on the black monitor under the TV amplifier.
- Wait until the delay & reset LEDs have gone out, then flip
one of the TV scan switches to ensure signal is comming through.
Leave both the scan switches upwards.
TELESCOPE IS READY FOR OBSERVATIONS
CLOSING DOWN
- Turn the TV amplifier and monitor off.
- 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.
- Put the Telescope in ENGINEERING MODE by pressing the ENG/COMP push
button or by typing
USER> eng
The button should now be
illuminated with an yellow light, indicating engineering mode has been
selected. If an audial alarm sounds, type
USER>ack
to mute
the alarm.
- Closing the dome top shutter
Always remember to bring down the lower
shutter first
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.
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.
FILLING CRYOSTATS - MORNING
As at the start of the night, the IDS cryostat needs to be filled:
- Fill the Cryostats. 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 DDS1 (90m) 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.
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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