Photo of a “Super Moon” from my bedroom window that caught a jet liner by serendipity.
Improvisation in Bach’s Tuning uses a preset tuning in Pianoteq 4 called Herbert Anton Kellner’s Bach tuning of 5 1/5 Pyth. comma and 7 pure fifths. In other words it is a very pure meantone tuning. Instructions for tuning your instrument to it can be found here. You can get some idea of Kellner’s argument based on the title page of Bach’s Well Tempered Clavier here.