SOFI Calibration Plan: Collimator

European Southern Observatory
New Technology Telescope

General :
Observations :
Operations :

Procedure :	Collimator Focus
Author :	SOFI team
Release :	12/09/99 : update 06/01/99 : creation

The collimator focus should be determine once every three months and it should also be checked after the instrument has been thermally cycled. The focus has to be computed for all of the SOFI filters and, besides a filter should be given, for each of the 6 imaging modes. These long templates can be executed, for instance, during cloudy nights or EMMI runs. The collimator focus has proven to be very stable, even after thermal cycling. The stepper motor values for the collimator are recoreded in the file /data/SOFI/SYSTEM/MISC/ICS/isiSystemSOFI.cfg.

Measuring the collimator focus.

Make sure MIDAS for PCO is running.

6 Observation Blocks are available in the directory /data/SOFI/SYSTEM/COMMON/OBD/CALIB :

    - SOFI_ima_tec_InstrunentFocus_LF.obd   for the "Large Field Imaging" mode ;
    - SOFI_ima_tec_InstrunentFocus_SF.obd   for the "Small Field Imaging" mode ;
    - SOFI_ima_tec_InstrunentFocus_SO.obd   for the "Spectroscopic Objective Imaging" mode ;
    - SOFI_ima_tec_InstrunentFocus_HR.obd   for the "High Resolution Imaging" mode ;
    - SOFI_ima_tec_Ins...Foc_LF_FE.obd   for the "Large Field and Focal Elongator Imaging" mode ;
    - SOFI_ima_tec_Ins...Foc_SO_FE.obd   for the "Spectroscopic Objective and Focal Elongator Imaging" mode.

Each of these Observation Blocks groups a set of 21 templates to determine the focus position for the 21 filters of SOFI.

The results are recorded in the file /vltdata/SPC/SOFI_tec_cal_InstrumentFocus.SPC.

If a focus position has changed by less than 2000 steps, do nothing. If it is more, you'll need to edit the configuration file.

Editing the Configuration File

In the directory /data/SOFI/SYSTEM/MISC/ICS/ make a backup copy of the configuration file isiSystemSOFI.cfg.

Bring up the ICS control panel from the tools menu of the OS panel.

From the commands menu of the ICS panel set all devices OFF. The name tags of instrument functions will turn red.

Bring up the configuration tool from the tools menu of the ICS panel.

Select the file isiSystemSOFI.cfg from the configuration tool and make the appropriate changes.

Press the load button and wait about 20 seconds for a window with an OK to appear.

From the commands menu of the ICS panel, set the instrument mode to STANDBY. The name tags of instrument functions will turn green.

From the commands menu of the ICS panel, set the instrument mode to ONLINE. The name tags of instrument functions will turn purple as each function is initialised.

Quit the configuration tool and ICS panels.

Archive the configuration file.

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