FEROS at the MPG/ESO-2.20m :: Procedural and Operational changes after installation of ADC

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FEROS on the MPG/ESO-2.20m

Procedural and Operational changes after installation of ADC

Overview

For an overview of the FEROS ADC project and it's commissioning see the ADC project homepage.

Acquisitions

The FEROS acquisitions template will always automatically set the ADC OUT and set the focus appropriately. This is necessary due to the vignetting by the ADC in the center of the TCCD field of view.

Observing with ADC OUT then ADC IN or vice versa

When moving the ADC IN or OUT, there is a change of focus and an change in the apparent position of the stars in the TCCD (the magnitude of the shift being a function of Zenith distance). Therefore a PopUp Confirmation window appears on the wferos workstation whenenver the ADC state changes in order to allow time for the focus to reach its correct value and for the guiding, if it is active, to recenter the star on the fibre

FEROS focus

The handling of the FEROS automatic focusing has been signifcantly improved.
The FEROS_img_cal_focus template has been modified so that focus sequences can be made either with or without the ADC IN. At the end of the sequence the resulting Focus Offset is written to a database point in the wferos environment. The appropriate value for the ADC IN or ADC OUT case (according to which configuration the focus was made in) is also written into a wferos database point.
The NOMINAL focus values, which can generally be used in case no actual focus template execution is possible, are provided in the following table:

ADC	Nominal Focus
OUT	1440
IN	1880

At the start of each FEROS_ech_obs_objsky and FEROS_ech_obs_objcal templete the appropriate DB value is read according to whether the ADC will be used or not (ADC is never used for OBJCAL observations due to the conflicts between ADC and SCSM) and then written to a database value in the w2p2tcs environment.
The TCS Control Panel has been modified to read this database value and use it for the focus offset. The database value being used is displayed in the TCS panel in the DB.FocOff output field. See image below:

If a nonzero value is entered in the FocOff field and then the Apply button is clicked this value will be used instead of the database value and instead of displaying the current database value in the DB.FocOff output field, "----" will be displayed.
To revert back to using the database value, enter 0 (zero) into the FocOff field and then click the Apply button. Be sure to enter an actual 0 and not an empty field as an empty field will cause the TCS panel to crash!
As always in the past the correction is only applied if a nonzero value of the AAFT has been Applied. For FEROS observations AAFT should always be set to 15, except as advised when making a focus sequence. For WFI observations the AAFT MUST be set to 0. Don't forget to click Apply after any change to the AAFT (or FocOff).
The "Set >" button will set the FocOff to the value which makes the Theoretical value equal to the current "Position (EU) value", useful if you have set the focus by eye by manually adjusting the focus by setting the position with the "Preset to" button.
Problems with the Automatic Focus adjustment:

The Automatic Focus adjustment only works when the PANEL is active, if the panel dies or hangs you need to kill the hanged one and start a new one, don't forget to enter 15 into the AAFT and the FocOff value if you were not using the database value and then click Apply.
Remember that it is possible to run more than one TCS panel. Therefore to stop Automatic Focus adjustment, the AAFT must be set to 0 (zero) in ALL the panels.

Switching from FEROS to WFI observations

When switching from FEROS to WFI observations it is now necessary to ensure that:

The ADC is OUT
The SCSM is parked
The M3 is in WFI
Set the AAFT value to zero and click Apply in the TCS panel

Due to features of VLTSW, this has not yet been reliably configured as an instrument setup from the OS panel, therefore making these changes should be made from the ICS panel, as it has always been done for the M3 control. To do this depends on the situation the ICS is currently in:

ADC is IN

In this case the SCSM must already be in the PARK position, therefore in the "FEROS ICS Control" panel:

Devices -> Deselect all devices
Select the ADCA device (click the radio button to the left of the "adca" entry in the "ADC" tab.
From the adca's list button select "OUT"
Select the M3 device in the "Motors" tab.
From the M3's list button select "WFI"
Click on the Setup button at the bottom of the panel

Ready for WFI observations.

ADC is OUT

In this case the SCSM can be anywhere, therefore in the "FEROS ICS Control" panel:

Devices -> Deselect all devices
Select the SCSM device (click the radio button to the left of the "scsm" entry in the "Motors" tab.
From the scsm's list button select "PARK"
Select the M3 device in the "Motors" tab.
From the M3's list button select "WFI"
Click on the Setup button at the bottom of the panel

Ready for WFI observations.

A checklist of these procedures is here.

Switching from WFI to FEROS observations

When switching from WFI to FEROS observations it is only necessary to:

Set the AAFT value in the TCS to 15 and click Apply in the TCS panel

Ready for FEROS observations.

Instrument Startup

Although there were software problems during the commissioning period due to conflicts between the ADC and the SCSM which affected the Instrument startup these were solved during the commissioning.
Thus, as at 2005-03-16, there are NO changes to the instrument startup procedure resulting from the installation of the ADC.
For completeness the workaround procedure required during the first days of the commissioning are repeated here:

FEROS ICS StartUp workaround
Note carefully, the following workaround procedure is OBSOLETE.
If normal ICS ONLINE fails due to failure to move SCSM then:
In the "FEROS ICS Control" panel:

Devices -> Deselect all devices
Select the SCSM device (click the radio button to the left of the "scsm" entry in the "Motors" tab.
Menu Devices -> Simulate HW, click Yes in the popup window.
Menu Devices -> ONLINE
Deselect SCSM device
Select ADCA device
Move ADCA IN
Move ADCA OUT
Deselect ADCA device
Select SCSM device
Menu Devices -> Use HW, click Yes in the popup window.
Menu Devices -> STANDBY
Menu Devices -> ONLINE

System should now be ready.

Instrument Operation

Normal FEROS operations

The instrument pretty much functions just as it always has except for the following constraints on the movement of the the ADC in fuction and the SCSM:

To move the ADC the SCSM must be in the PARK position (or at an encoder value less than 2000eu (such as is the case after initialisation and before being moved to any of the four defined positions (PARK, BOTHFIBS, OBJFIB and SKYFIB).
To move the SCSM the ADC must be in the OUT position.

As for the initialisation, during the commissioning period, there was a software problem which meant that after moving the ADC the SCSM could not then be moved until it was re-initialised.
This problem was solved by IKa of SWC by implementing an automatic re-initialisation of the SCSM whenever it is requested to be moved after the ADC has been moved since the last initialisation. This does not cost much time since if the ADC was moved the SCSM must have been in the PARK position and therefore the initialisation takes only a few seconds. Moreover it will only be needed during the night for switching between OBJSKY mode observations where the ADC is used and either OBJCAL mode observations or internal calibrations.
Again for completeness the workaround procedure required during the first days of the commissioning are repeated here:

FEROS workaround to get SCSM to move after having moved the ADC
Note carefully, the following workaround procedure is OBSOLETE.
In the "FEROS ICS Control" panel:

Devices -> Deselect all devices
Select the SCSM device (click the radio button to the left of the "scsm" entry in the "Motors" tab.
Menu Devices -> OFF
Menu Devices -> STANDBY
Menu Devices -> ONLINE

It should now be possible to move the SCSM, at least until the ADC is moved again.

EUROPEAN SOUTHERN OBSERVATORY La Silla - Science Operations Department