Surviving Trial and Error: Aquatint Step Bite

"Aquatint" is a method for creating?areas of even tone, similar to?watercolor washes,?on an etching.

In fact, early printers called it "aquatint" because its effects reminded them of watercolor. Artists as diverse as Goya , Picasso,?David Hockney, and Chuck Close have done great things with aquatint.

It starts with a metal plate, powdered rosin, and an aquatint box.

This is rosin. It's made by boiling pine stumps and distilling the resin. (Not by me! I leave that job to the experts.) Those lumps?look like rocks, but rosin is very brittle.?You can easily?pound it into powder.

The finer your powder, the more delicate your etched tones will be, but pound it too fine and you won't have much tone at all. It's good?to mix some?coarse powder in with the fine stuff.

The next part of the process happens in a box.

Here is my home-made aquatint box. I sprinkle a few spoonfuls of?powdered rosin onto the bottom.?Then I lower the plate on its shelf inside, and close the box. It's built so that, when I?put on the lid,?the?long handles stick up through the top. I use?the handles?to?rapidly move the shelf up and down. In the resulting turbulence, the?powdered rosin rises up, then settles onto the?plate.

You can see the powder on the plate after it has been in the box.

A look at the black board after the plate is lifted shows how much rosin landed.

Even though very little rosin escapes from the box, the powder can be hard on the lungs. This mask may be more than I need, but it works great!

The next step is to melt the rosin so that it sticks to the metal as tiny individual dots.

I use a hot plate, but some people use a blowtorch or a specially constructed oven.

Once the rosin dots have cooled and hardened, I immerse the?plate in an etching solution. The?corrosive liquid will "bite" away the unprotected copper between the dots.?Later, when the plate is inked for printing, the bitten areas will hold ink, and will print as a toned shape.

This is the etching solution, ferric chloride (an iron salt).

For really big plates, I have the larger tank. In this case, the smaller container is just right.

If I want?some toned areas to be?darker that others, I can immerse the plate more than once. That's called a "step bite."

The first step might be a short bite, for a light tone. Before the next bite,?I brush a protective material called asphalatum over some of the bitten area. Then I return the plate to the solution, to be bitten more deeply.

A?step bite test?shows?how much darker the tone will be after different?lengths of?time in the etching bath.

In the photos below, I am testing?two kinds of bite: aquatint etching and line etching.?The aquatint plate, with melted rosin, is on the right. It will print as a series of shapes.

The plate on the left will print as a series of line drawings. First I covered it?with a waxy resist, then I scratched some doodles through the wax with a sharp point. Where I scratched, the etching solution will bite.

These plates have already been through the first step, a 15 second exposure. Now they will go in for another 15 seconds, for a total of 30. The next step will add 30 seconds, for a total of one minute, and so on through the process.

After each immersion,?I paint on a thick band of asphaltum, then wait about an hour for it to dry.

I add time in 2, 4, and 5 minute steps, for a total of 50 minutes of exposure. I keep a running record so I don't?mess up the timing.

In between exposures, I get other stuff done.

The numbers are backwards so they will be forwards when printed.

Here the plates are drying after their 5th step in the bath, 4 minutes total exposure.

And here they are after the 10th step in the bath, 16 minutes total exposure,.

These plates will be my reference for how long to etch plates in future projects, depending on how darkly I want their tones or lines to print. At the same time, I am also teaching myself some?finer points of the?aquatint process.

Alas! Learning?involves plenty of??trial and error.

First good news, then not?so good news, then more good news:

Yay! This line-etch test came off the press looking great. The progression from light to dark ?showed up clearly. I can definitely use this print as a guide in the future.

On the other hand, the aquatint test print was a little disappointing.

Apparently the plate was slightly bowed in the middle, so that the rosin heated unevenly. That caused some rosin dots?in the middle to dissolve, creating a space that held less ink.

But it wasn't all bad.

The first 5 exposures produced delicate, even tones across the plate, and I got deep, dramatic dark tones at the end of the test. No doubt I will want to create just those effects in the future, and now I know how.

I am planning a new, ambitious project that will include lots of aquatint, so I need to get up to speed.

Later this month I will continue my study of?aquatint techniques with help from the master printers at Crown Point Press, in San Francisco. It's a great opportunity, and I will tell you all about that adventure when I return.

Want to follow me while I am there? Look for my posts?on?Instagram (carollambertarts) and FaceBook (Carol Lambert Paintings and Drawings).

Have I told you how?grateful I am for your interest and support? I can't say it often enough.

I love bringing you into my studio and showing you these arcane processes. Is there something you are curious about? I am always looking for ideas for this blog, and I would be happy to have your questions.