Once the cube has been created, a flag file is written to indicate to the telescope POINTING_FOCUS task that processing is complete. The recipe also makes its own estimate of the best-fit focus position by fitting a parabola to the fitted peak flux densities at each SMU position. The solution is written to a log file, log.focus.

This primitive is largely the same as REDUCE_FOCUS with minor modifications to handle data as they are taken.

• The best-fit focus position is written to log.focus.

• The minimum number of images referred to above is defined as the mean number of images obtained for each of the preceding focus positions. The recipe may fail to produce a cube if the pipeline does not receive enough data, even once the observation has ended. This is because the OBSEND flag in the FITS header will only be true for the final subscan and thus the summit pipeline may not see it.

• No data are displayed until the cube of focus images has been created.

• The bright_compact config file is used.

• See also REDUCE_FOCUS.