During the etch, I note the time the plate spent in each solution, the time when shadow, midtone, and highlight etching first occurred, and the total etching time. Total etching time is usually between 20 and 30 minutes, depending on when the shadow tones first started etching. Since etching generally speeds up as it progresses, highlight etching at the end must be brief to retain the light tones visualized for clouds, snow, and similar areas of the print. At what I hope is the right moment, I end the etching by immersing the copperplate in cold water. Rubber gloves, apron, and ventilation are essential for this.
Ferric chloride is best when 'seasoned' or after it has been used for etching a few copperplates.
After each etching session, I top up the more dilute solutions with the more concentrated ones. In that way, each solution retains a relatively constant strength and a similar amount of the impurities that gradually accumulate. Etchings Browse .