The techniques are very similar and the actual printing is the same, but engravings tend to be a bit more stiff in the expression as the cutting in a hard surface makes it harder to make quirky lines. So the horisontal lines in the sky is a sign that it is engraving. Engraving tend to be more planned with clever ways of crosshatching while etchings look very much like line-drawings and making them is just like drawing with a very thin line.

Rembrandt preferred the much more organic lines of etchings, while engravings where the preferred media for mass-produced images because the triangular cut were more durable than the square etched ones.