In 1866, he began to experience financial difficulties and left the Academy to continue his studies himself, painting scenes of Limfjord and the moors of Jutland.
His works depicted country life in Jutland, most of them with an emphasis on animals and local figures.
He had a talent for form and detail but his use of colour was rather dry, diminishing the appeal of his paintings to the general public.
As the years went by, Smidth's style developed considerably, earning him the Neuhausen Prize in 1877 for En fremmed spørger om Vej i Bondegaarden paa Heden which was not only technically impressive but showed a fineness of tone.
In retrospect, his paintings are free of historical or mythical figures, they do not interpret scenes along the lines of the Skagen Painters.