IANAE but what I use is log_10 by increments of .1. The starting point is that 10^.1 is roughly 5⁄4. (It’s actually ~1.259 rather than 1.25.) You get, basically,
1
1.25
1.57
2
2.5
3.1
4
5
6.3
8
10
and you can pretty closely regenerate this with 10^.1 = 5⁄4, accelerated by remembering 10^.3 is 2 (which pins down 4 and 8).
IANAE but what I use is log_10 by increments of .1. The starting point is that 10^.1 is roughly 5⁄4. (It’s actually ~1.259 rather than 1.25.) You get, basically,
1 1.25 1.57 2 2.5 3.1 4 5 6.3 8 10
and you can pretty closely regenerate this with 10^.1 = 5⁄4, accelerated by remembering 10^.3 is 2 (which pins down 4 and 8).