- An obnoxious sounding buzzer will go off. Don't panic - compose
yourself.
- Stop or Abort the scan in progress. If the scan is in the reverse
direction and has not yet passed through ZPD then it is useless and
should be
aborted. However, if the scan is in the forward direction it may be
worth saving, depending on the resolution which has been achieved up to
the
point of the servo unlock.
- Once the scan has been terminated, push the ZPD servo button on the
main control panel. The carriage will return to mechanical ZPD, and the
buzzer will eventually go off.
- Reenter fringe mode.
- Refind optical ZPD, and resume observations.