[1] His sentimental paintings of poor people enjoying nature became a posthumous high fashion, notably in the 1870s when his market price rose higher than Constable (Cromer Sands, £3780, 1872) and stayed so until 1894.

[1][5] In 1817 he visited Paris with Leslie and Washington Allston and painted The Departure of the Diligence from Rouen, and the Scene on the Boulevards (both sold privately) – these were exhibited at the Royal Academy in 1818.

In 1826 he painted The Fisherman's Departure, (engraved by Phelps), and in 1828 made a tour of the Netherlands and Belgium, living for short time in Boulogne in 1836.

In September 1836, Collins left London for Italy, where he remained for two years, occupying himself with advancing his knowledge of painting, but he had to return due to illness.

He then began a series of pictures depicting Italian life, including Poor Travellers at the door of a Capuchin Convent near Vico, Bay of Naples[6] and A Scene near Subiaco, both exhibited at the Royal Academy in 1839.

In 1840 he visited Germany and in 1842 the Shetland Islands, the latter inspiring a series of illustrations for Sir Walter Scott's novel Pirate, which appeared in the "Waverley" edition of the book.

Ruskin commented, "I have never seen the oppression of sunlight in a clear, lurid, rainy atmosphere more perfectly or faithfully rendered, and the various portions of reflected and scattered light are all studied with equal truth and solemn feeling."