Takes an exposure without opening the CCD shutter, and transfers the data plus headers to an HDS file on the system computer.
2=to: 2!:}Format: DARK <channel> <time> ["<string>"]
2=to: 2!:}Channel: The name of the CCD data acquisition channel to be used.
2=to: 2!:}Time: The exposure time in seconds
2=to: 2!:}Title: A title for the observation (optional)
2=to: 2!:}Examples : DARK PFIP 9999 "Measuring dark counts"
2=to: 2!:}Comments: As for the RUN command, except that the CCD shutter is not opened, and the observation type is set in the headers as being a DARK exposure.