Upstairs on the first floor where the fine art collections are displayed is as impressive as the ground floor: the same attention to a broad narrative, interspersed with occasional display cases holding decorative arts, a reverse of the policy on the ground floor; some sculpture; they decided to keep a broadly chronological layout.
Johan Christian Dahl studied in Copenhagen, taught landscape painting in Dresden and encouraged the establishment of Norway’s National Gallery:-

Caspar David Friedrich, Greifswald in Moonlight (1817):-

Adolf Tidemand, Portrait of a Farmer from Vossevangen (1855):-

I like Karl Jensen-Hjell’s portrait of the artist Kalle Løchen, At the Window (1887):-

Christian Krohg, Sick Girl (1881):-

I don’t recommend trying to see it all at once !