Small Gems: Etchings selected by Brad Hart, Operations Director

BRAD HART: Everything about A Little Linger is just exquisitely done. In an etching the artist is using a needle to scratch through an acid-proof resist and make lines, and for an aquaint they're also using a powdered rosin to create a tonal effect. The super soft tonal range going across the background, that's a very difficult thing to get to work in etching.

CHRISTINA ZIEGLER CAMPBELL: This was Katherine's first etching, which is crazy because of the number of techniques. A lot of times we'll start someone out with one easier technique like hard ground etching. But with A Little Linger we really threw her in: soft ground, hard ground, creep-bite.

BH: With creep-bite, you're gradually lowering the plate into the acid, and the longer it's in the acid the darker the tones will be. If you do it wrong, you get hard lines instead of that gradual shift you see on the wall in the background of this print.

CZC: And the asphaltum resist, which prevents the acid from reacting to the copper plate, is applied with an airbrush, which preserves the delicacy of that aquatint gradient. A really good aquatint looks like a matte velvet, which they accomplished here.

BH: There was also a lot of scraping and burnishing done to the plate, which is visible on the skin of the figure. In an etching you're creating texture on the plate, and that's what holds the ink, so if you smooth that texture back out you can create highlights like that.

BH: Aquatint is the most direct way of getting tone onto the plate. The ideal is to get a 50% covering of fine rosin dust on the plate.

CZC: Rosin is a powdered tree sap. It has a really low melting point, which is why you could fuse rosin to a copper plate by using a low flame like a torch or a hot plate.

BH: The best way to distribute the rosin is to place the plate in an aquatint box, where the dust is stirred up and then lands evenly on the plate. Then you heat up the plate, which melts the little rosin dots onto the plate. Then you look at it with a magnifying glass to make sure it's distributed evenly. When you etch the plate, you stop out the parts that you want to be the lightest first—the highlights on the face, the flowers, the lightest parts of the background—and then repeat the process for each tone, stopping out the darkest parts last.