Cornelius Norbertus Gijsbrechts (c. 1610 - after 1675), Trompe l'oeil. The Reverse of a Framed Painting, 1670
Upon cursory inspection this painting by Cornelius Gijsbrecht looks like its counterpart on the wall.
The difference is that the door can in fact be opened. This time our eyes are not deceived; unlike in other trompe l’oeil paintings by this Flemish artist.
The cupboard in real life
As you turned the key and opened the door you would look into a cupboard where the ivory vessel and gold equestrian statue would be on display in real life.
The back of the door shows the back of the glass pane with notes and letters inserted. The ivory vessel – and perhaps the statuette as well – was created by the German artist and ivory carver Joachim Henne. Like Gijsbrechts he worked extensively for the Danish court. The room features a similar equestrian statuette and statuettes carved by Henne and other artists from the period