James Ensor used the etching technique as well as the more complicated technique of dry-point engraving. Both are intaglio techniques in which the image is incised into the copper plate and then filled with ink. The surface of the plate is then wiped before the paper is put on top. The ink lines on the paper have a tangible relief. The way in which the image is put into the plate is different. In etching the plate is covered with etching varnish and the image is drawn into the varnish. The plate is then immersed in an acid bath which ‘bites' the exposed metal, producing incised lines. In dry-point engraving on the other hand the incised lines are scratched directly into the metal plate with a sharp needle. The sharp, pointed needle-like instrument used leaves a groove in the metal. Because this process creates a slightly raised ragged rough edge on both sides of the line, the printed line has a distinctive velvety look. The result cannot be corrected. Although the lines are less clean, they can, as James Ensor has done, be exploited artistically. After all, dry-point engraving allowed the artist to make the most of his agile, sensitive and subtle drawing method.
Ensor was not a true etcher such as Armand Rassenfosse or Félicien Rops. He was hardly interested at all in the engraving technique. Whenever he experimented, the result was most of the time not very convincing. The print Starry Sky above the Graveyard is a good example. James Ensor was well aware of his lack of skills, as becomes obvious from the following extract from a letter to Valère Gille: "I have not mastered the profession of etcher at all. I draw and engrave neatly but apart from that I leave it all to chance. I do not know all the tricks and dodges of the biting process, as a result of which I have damaged quite a lot of plates and I have unnecessarily spoilt my eyes." And so James Ensor used several professional plate printers from Brussels, first Evely, later on Charles Vos and father and son Van Campenhout by turns, to execute his prints..
Except for landscapes and those prints which were based on existing compositions, Ensor probably made a preparatory drawing for most of his engravings, sometimes merely a sketch, at other times more detailed drawings. Their format was overall quite small. As far as the style is concerned the etchings show a remarkable diversity: prints with brutal, nonchalant lines alternate with plates which show a carefully developed drawing. Certain etchings have been influenced by Rembrandt's claire-obscure technique, while others have a purely impressionist or even pre-expressionist nature.