# Pre-amble

IMAGER is an interferometric imaging package, tailored for usage simplicity and efficiency for multi-spectral data sets.

IMAGER is *** NOT *** MAPPING

IMAGER was created because the initial infrastructure for imaging in the MAPPING program was not adapted to the implementation of imaging methods that became possible and/or were required for NOEMA (and useable for ALMA), such as self-calibration, wide band imaging, or routine processing of Mosaics and Short spacings.

The IMAGER design takes great care of efficiency, by using parallel programming and minimizing Input/Output on files. This lead to a concept with a single READ of data, a few (in general only 2) simple processing commands with built-in intelligent parameter guesses, a visual user control, and a single WRITE of the results once the user is satisfied of it.

We took the opportunity to revise and streamline the user interface, providing access to all tools through simple commands. A special effort was put on the visualization tools, which provide enhanced speed and capabilities, yet preserving a very high level of compatibility with those previously offered in MAPPING.

IMAGER was derived from MAPPING by S. Guilloteau. T. Jacq and E. di Folco made numerous suggestions about the user interface, and helped testing and documenting the program.