Two things about it are wrong, and the name is only the first. It is not a night scene: a darkening varnish invented the night and the wrong name stuck. And it is not the painting Rembrandt delivered in 1642, because in 1715 somebody trimmed it on all four sides.
The varnish made the night
Rembrandt's subject was a militia company mustering in daylight. The formal title is Militia Company of District II under the Command of Captain Frans Banninck Cocq, which is nobody's idea of a name for a picture, and that is half of why the wrong one won.
The daylight is still provable from inside the painting. Follow the captain's outstretched hand and you can see its shadow falling across the pale coat of the lieutenant beside him. Nothing casts a shadow like that at night. By the end of the eighteenth century the varnish had gone brown and everyone called it the Night Watch; it was cleaned in the 1940s, the daylight came back, and the name did not move an inch.
1715: the trim
It was moved to Amsterdam's town hall, did not fit the wall, and was cut down, probably to get it between two columns. The museum's measurements of what went: 64.4 centimetres off the left edge, 23.3 off the top, 11.3 off the bottom and 7 off the right. The strips have never been found.
What was on them is known, because Gerrit Lundens painted a small copy of the whole composition within a few years of the original, commissioned by the captain himself. Set the copy beside the painting and the damage is obvious. The cut also moved the middle: the two men everybody thinks of as the centre of the picture were pushed there by a knife.
Printed back on, in 2021
Since 2019 the Rijksmuseum has been working on the painting in public, behind a glass wall, and calling it Operation Night Watch. Visitors watch the research happen. It has already turned up the rough sketch Rembrandt laid straight onto the canvas in a chalky beige paint, and found that he soaked the canvas in a lead compound first, which nobody has ever seen him or his contemporaries do.
In 2021 it used the Lundens copy together with a neural network trained on Rembrandt's own brushwork and colour to reconstruct the missing strips, printed them onto panels and hung them around the canvas. For a few months the composition was whole for the first time in three hundred years. Two militiamen and a child came back on a bridge at the left, a helmet came back on the right, there was more step and more arch, and the two central figures were no longer in the centre, because they never had been.
Three hundred years of missing edges, put back for a few months in 2021. This one comes whole, nothing trimmed.
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