[4] His chief peculiarity consisted in the fineness of his mechanical finish, which extended to depicting even the almost invisible furze of hair growing on smooth skin.
At the time Altona was part of the Danish kingdom, its second largest city after Copenhagen and famous for its religious tolerance.
[7] His convalescence was slow and to cope with boredom Denner started to draw and copy paintings by Berchem and Bloemaert.
In 1712 he married and the next year he moved to Hamburg when Altona was destroyed by Magnus Stenbock during the Great Nordic War; in 1714 he made a trip to Amsterdam; in 1715 to London; in 1717 to Copenhagen.
While in Hanover, Denner was invited to England, but first he met with Adriaen van der Werff, and showed him his painting of an old woman.
[7] Also in London the painting caused great excitement and it was sent to Charles VI, Holy Roman Emperor.
In 1734 he rented a house in Amsterdam, but was busy painting for Christian Ludwig II, Duke of Mecklenburg in Schwerin.
He moved there in 1736 and painted the wealthy Dutch banker George Clifford, a keen plant-collector who had invited Linnaeus to live on his estate Hartekamp.