Primitive Screwhead said:
the dwarf spends his last charge in the minutes before 'reset time'. That charge cannot be used as it falls into the 'within 8 hours clause' and his lenses rest to full with 4 charges.
Only 4 for the whole day? Or just an 8 hour delay until he gets the 5th too? If the latter, then even when using the simple midnight refresh with an 8 hour clause, if he activates his eyes at 17:00, 18:30, 19:45, 21:15, 22:30, and 23:45, and each gets delayed 8 hrs seperately, you would basically still end up with a complex chart of staggered recovery times; 1:00, 2:30, 3:45, 5:15, 6:30, and 7:45. And similar for each daily-use item/ability possessed by each party member.
I realize that's overly picky and unneccessary, most DMs will just refresh when convenient, and a convenient break usually pops up anyway. But I'm just trying to figure out how it all should work "in principle", so I know what needs to be smoothed-over during gameplay.
A simple overnight ruling works good for a standard party, but when faced with non-sleepers running around in places with no day or night, like Underdark or some Outer Planes, it gets trickier. Especially when the party is waiting for things to refresh, and wants to figure out when they can expect to use things again. I guess that's the real reason I brought this up.