Keywords: imager

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## Transfering the solution to other uv data sets.

An important use of the Self-calibration is to compute a calibration solution using wide bandwidth data (continuum data, where signal-to-noise can often be maximized) and apply it to high spectra resolution (line) data.

The technique is quite simple. Solve for Self-calibration using the wide bandwidth data as usual, and save the results (gain tables) using the magenta`WRITE CGAINS` command (eventually one for each of the `PHASE` or `AMPLI` steps of Self-calibration).

At any time, you can read back these gain tables using magenta`READ CGAINS`, read an uv data set with magenta`READ UV` and apply the gain solution using command magenta`APPLY`. Since Self-calibration normally corrects for atmospheric errors, the derived `phase'' correction is in general here to compensate for a pathlength change, i.e. the corresponding phase correction should scale as Frequency. magenta`APPLY DELAY` instructs [rgb]1,0,0IMAGER to take this effect into account.