No, I didn't sit on Gwithian beach and paint this on New Years' Day (it would have been too cold!). I sat in our dining room and painted it today, from one of a series of photographs that I took on New Years' Day.
It's a long time since I painted from a photograph. It's not something that I usually like to do, but the sea presents a few challenges without the aid of a camera (not least it being quite a long way to go; even the closest bit of coast is too far to give a reasonable amount of painting time during a school day), as did the weather that day. The photograph was a 12MP digital image that I printed out at A4 size. I also printed a couple of the other shots at a smaller size, but I didn't really refer to them.
New Years' Day this year was dull in Cornwall, and my photograph was very nearly monochrome, so I deliberately brightened the image up with blues and greens - and a hint of rose madder. No point being too slavish to a photograph. I do think that I should have worked bigger; this was a large subject for the size of board that I chose, particularly as I applied the paint with a knife.
Edit: See also: Godrevy Lighthouse, Cornwall, New Years' Day 2012 - bigger version
Oil on board, 12 x 10"
The board is a commercially prepared canvas board.