Always start by picking a band (mouse right click in one of the distribution plots, usually the first one, menu "Pick band"). It represents the band to preserve. All samples falling outside this range are rejected from the statistical computation after a click on "Reject" button.
All is based on arrow key and modifier SHIFT
- Up/Down arrows: move to the previous or next frequency.
- Left/Right arrows: move lower bound of the band up and down on the value scale.
- SHIFT+Left/Right arrows: move upper bound of the band up and down on the value scale.
- SHIFT+Up/Down arrows: move to the previous or next frequency after rejecting the samples outside the range.
On the first run, when no bands are defined and when SHIFT is pressed together with Up/Down arrows, the band at the previous frequency is used as a reference to suggest the band for the current frequency. The center of the band is moved by a quantity equal to the difference of the unfiltered means at the two frequencies.
The manual filter is then rather quick with usually just pushing several times SHIFT+Up arrow, and exceptionally adjust the size of the band with (SHIFT+)Left/Right arrows.