I kept finding that I liked some of the more detailed earlier stuff better - they would be talking about how he developed from x to y, and I would be thinking 'I kind of liked x'. I do love the GWR train one, though.
I checked, the painting they discussed was Norham Castle, Sunrise (https://www.tate.org.uk/art/artworks/turner-norham-castle-sunrise-n01981). Have to admit, I love it...
no subject
no subject