The Johan Zoffany exhibition at the Royal Academy of Arts has at least one picture of Luton.
It shows the three daughters of Lord Bute in 1763 when he was prime minister. The girls are grouped round a tree at Luton Hoo near the archeway entrance.
A painting of the sons is in siimilar countryside although is it not confirmed at Bedfordshire.
Also by a tree, athough in Italy, is the 3rd Earl Cowper. His statley home was Panshager Park at Cole Green near Hertford (see page 54) but he spent most of his time in Florence where Zoffany caught up with him.
Johan Zoffany RA: Society Observed is at the Royal Academy of Arts in Piccadilly from Saturday 10 March to Sunday 10 June; admission £9 (conc £7).