Why is fog transparent when you are in it but opaque when you are outside it?

Question

Whenever I see some fog, it usually is very opaque when I am far away, like cloud, but when I am it, it’s far more transparent, though obviously visibility is decreased

In: Physics

Answer 1

The more fog between you and the object you want to see, the less you will see it.

If you look at fog from afar, you’re likely looking through a lot of fog (because there is just nothing else there but air). But if you’re inside, you can focus on objects that are close enough to still see them somewhat, and you’ll just ignore anything farther away.