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Problem: ThAr calibration spectra seem to be very faint.

  • Solution 1: the mirror directing the light to the calibration fiber in the MAXnet cabinet may be stuck. Restart the spectrograph a few times (acectrl --stop, acectrl --start).
  • Solution 2: if it does not help, notify the support astronomer. A replacement for the ThAr lamp may be needed.

Problem: bright features (tipically bright Ar lines above 6000 Å on the ThAr spectra) cause massive saturation in whole columns of pixels.

  • Solution: this problem may be related to the erroneous behavior of the preflush sequence of the FLI camera on the spectrograph bench. A possible workaround is to read a few bias frames out after every image.

Note: since the replacement of the spectrograph CCD, this phenomenon became very rare.

Fig. 1

Problem: Spectrum focus seems to be on 0 value.

  • Solution: In case you remember the previous value of the spectrum focus, use the acectrl --spectrum-preset-focus value command. If you don't, the default value is 11600, and large deviations from this are highly unlikely, thus it might be used as well (also note that end-switches are installed).

Problem: Switching spectrograph mode does not work, only appears to.

  • Solution: This can happen after a longer power failure. Stop and start the spectrograph a couple of times. It may take several tries.

Problem: The QSI guider camera stopped working, and gives the /usr/local/bin/qsictrl: connection to camera failed, aborting. error message.

Also, the camera probably beeps loudly, and the led on its back glows red.

  • Solution: manual reset (unplug the camera and plug it in again). Th camera can be found on the side of the frontend (if the telescope is in home position, it is on the northern side of the frontend box). Be careful: the camera can easily be moved along the focal axis with a careless touch.

Problem: when trying to take an exposure ccdsh gives a sequence: imaging device is busy, waiting... or module: unable to initialize module 'mod_fli_camera.so':via initializer '__init': unable to access and/or initialize FLI CCD camera device. message.

  • Solution: notify the support astronomer (or restart 172.31.171.98, Fig. 1., located in the RCC "observing room")

Problem: the spectrograph CCD cannot be cooled down or gives nonsense temperature values.