The first tape copy of the data (the D-tape) is kept by the observatory and stored in the data archive. Currently D-tapes are in FITS format on DAT. It is the responsibility of the observer to write the D-tape. To do this log in to the observing computer LPVE (VAX) as OBSERVER (password known to local staff). Type STARTFITS to initialize FITS procedures. The tape must be mounted foreign (e.g. MOUNT/FOR MUA1:). New FITS tapes have to be initialised with FITSINIT, and then they may be written on with WRITE_FITS, in each case follow the prompts. WRITE_FITS will append to tapes (i.e. existing files will not be overwritten unless FITSINIT is issued first), and about 400 full frame Tek 1024 images can be stored on a single DAT.
The Observer's copy of the data (the C-tape) can be a copy of the D-tape, which can be requested by filling in a tape copy request form, a Backup of the data directories, or a separate DAT or Exabyte written in exactly the same way as the D-tape. The FITS writing routines can be run from any username, and two tapes may be written simultaneously (see Sections 4.9 and 7.1 for more details).