Tea break from the shop so I'll answer your question...
Generally speaking we don't really know what pitch they tuned the lute at, all reliable recordings have been lost, too many wars and such
. The concept of pitch was much more arbitrary than it is today so...Probably G is the best reference point taking into consideration the string length as I mentioned above. And to reiterate, the longer the string length the lower the pitch and conversely the shorter the string length the higher the pitch.
1 - g, single string usually. If you see a Vihuela (Spanish instruments like guitar, tuned same as lute) often double/unison
2 - d, double/unison
3 - a, double/unison
4 - F/f, double/octaves. Very occasionally this course can be F double/unison. Most players by far use the octave here as well.
5 - C/c, double/octaves
6 - G/g, double/ octaves
Unlike the modern 12 string guitar which usually has the octave string on the top of the octave (towards the player) the lute has the octave on the bottom (away from the player).