i'm purchasing a matte box, and what to purchase some filters, and some more NDs, graduated and non-grads, but i don't want to duplicate what the 20x lens comes with... the lens ND markings read: 1/6 & 1/32
1/6 = less light & 1/32 = even less light

but when everyone else markets their filters:
ND ---- f-stop reduction
.1 ------ 1/3
.2 ------ 2/3
.3 ------ 1
.5 ------ 1 2/3
.6 ------ 2
.9 ------ 3
i get the math .1 = 1/3stops, thus the greater the ND number - the less light allowed... but by the 20X lens markings, 1/32 < 1/6 (mathmatics) so this would mean the 1/32 should let in more light - it doesn't... so can someone explain to me the markings or offer their f-stop equivalents...
thanks,
Lonnie