From memory the specifics were a dawn departure downstream from Rouen, to ensure we took the travelator of a tide that flows with gusto on the tidal river Seine. In the image you can just see the hints of mist, but not long before or afterward tendrils of thick fog were curling over the rails and knitting themselves into a blanket to obscure even the bankside, just a few scant metres away. It was technically illegal for a leisure boat to proceed in such circumstances, given the commercial traffic on the river, but on 70-odd miles from Rouen to the sea there are few if any places suitable for pulling over and tying up, even on a steel motorboat. And so we put the radar on and spent a concentrated hour or so until the sun got going and broke through.
These days it would be very interesting to see how a FLIR infrared thermal imaging camera would have coped with the conditions; I’m hoping to see first-hand before too long now, as soon as we have demonstration units in play.
Meanwhile the much older technology of 35mm Fuji film reminds that the summer is but a few months away and adventures hopefully beckon.