## IMAGER for previous users of MAPPING

IMAGER offers a number of advantages against MAPPING : higher speed, simpler and more consistent user interface, integrated pipeline processing, and a number of improved image analysis tools. However, the principles have not changed. Most commands remain quasi identical in IMAGER and MAPPING, with basically the same control parameters.

Actions which were driven by widgets have often been replaced by simple commands (with intuitive names). A quick look at the HELP will guide you to the commands that will do what widgets were doing before. So you can skip over the fundamentals, and focus on the new tools offered by IMAGER. In practice, for you, commands will make fairly reasonable choices of default parameters. Just do not forget to WRITE your data.

In short, the biggest changes for MAPPING users are
- the lack of use of the GO command, and thus of the NAME and TYPE variables
- the suppression of MAP_RA MAP_DEC MAP_ANGLE and UV_SHIFT which have been replaced by MAP_CENTER
- the replacement of all tasks by simpler, standard commands.

Changing the defaults may be needed only for practical reasons:

- Optimizing computation time. This includes adjusting the field of view (variable MAP_FIELD), resampling in velocity (command UV_RESAMPLE) and time averaging (command UV_TIME)
- Comparing strictly different images (on a pixel per pixel basis). Adjusting MAP_SIZE and MAP_CELL will become necessary in such a case.

The names of variables and most commands have been kept from MAPPING, old names appear in the HELP whenever they have been replaced.

Subsections

- Forget INPUT and GO command