Acute vision is incredibly nuanced.

Here is some information, but even as many rangers as I've played I suspect it is incomplete and/or not 100% accurate.

Non-wood-elf ranger: See camo. Scan invis. See hidden in some non-civilized terrains. Scan hidden in other non-civilized terrains. (Other caveats exist based on terrain)

Wood-elf non-ranger: Never played a non-ranger wood-elf, so can't say. Likely see invis in forest like Ibuki said.

Wood-elf ranger: See invis in home terrain (not forest if you aren't forest home terrain). Otherwise same as non-wood-elf.

Sportsmanship killed CF