European Southern Observatory New Technology Telescope

General :
Observations :
Operations :

EMMI - RILD Focus Flexure Monitoring

The purpose of this procedure is to monitor the mechanical flexures produced  into EMMI - RILD with the rotator at different angles measuring the shifts of image on CCD in x,y and focus.

The procedure takes n exposures of the pinhole seen through Focus Wedge , changing the rotaror angle by a rotator step editable in the RildFocusFlexure.obd, then, measures the displacement of the pinhole image on the CCD in x and y directions for the leftmost image and dy ( defocussing)  for the rightmost image
(for  spectroscopy, x axis is along the dispersion and y axis is across the dispersion).

The RildTiFlexure.seq template moves rotator b from wemmi.

Procedure:

Check that pinhole is installed:

Load Rild_tec_Flexure.obd in BOB :

If you wish, change the rotator step angle :

 Check that rotator may rotate safely :

  it is advised to keep light on in EMMI room and switch camera video watching to EMMI.

Check that

• no interlock is on
• M3 is looking side B

• Start template in BOB
• After first exposure, in MIDAS/PCO display window, adjust boxsize to about images
  separation, click lower then upper image, then click twice mouse middle button.
• check that rotator is moving from -180 degreed to 180 degrees and back stepwise.
• At completion pick up 2 printouts and store them into maintenance result binder
• Compare to previous  results and report any significant variation .

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