|When no source passes the filtering condition, Warning noSourcesSelected is issued, then if the output mask file already exists, this taks raises this error to abort.|
|No source is selected after the specified filtering is applied. In other words, all the sources are filtered out.
corrective action: No source is selected hence it stops.
|All the sources in an input source-list are more than 90 degrees away from the field of view, and are hence ignored.
corrective action: All the sources are out of field of view.