Career
In Estonia, he painted figural staffages on large Põltsamaa landscapes and depicted Estonian peasants in the 1780s. In Mainz and Frankfurt-am-Main he was known mostly as an etcher and a landscapist. Welté was a typical artist of the Enlightenment – pensive, developing and nonconformist.
His most important work, the illusionist fresco wall paintings in the hall of the Lohu manor covering 27,6 m², were discovered in the 1960s under the Grisaille pictorial fresco wall papers on the theme of Don Quixote, printed by "Jacquemart & Bénard" in Paris, France.