As I'm always in foul weather, they call me "foul weather Otto" or just "Foul Otto" not sure if that is a reference to the weather of my temperment
. I often surface near a convoy when the visibility is only 900 meters. This is when I am certain I am still outside the convoy. So I do get within close range in fog but its out of necessity and at the outer edge, since you can usually see 100m to 200m further on the surface than through the periscope in fog.
In low visibility if I am trying to get to the center of the convoy. I stay submerged because you have little time between sighting a ship on your 270 or 90 bearing to get more depth if you need to in order not to get rammed. I do keep an ear on my hydro but in the middle of a convoy you can have readings from your 50 to your 120. This can be an adrenaline rush too. Trouble is in fog you basically just have to take what is in front of you.