This process enables you to create a wide range of tonal areas
on your copper plate. Depending on the way you apply the aquatint, they may
be flat tone, or graduated tone. Stencils can be used to define shapes or mask
out areas of the plate.
Aquatints can be used as a sole means of creating an intaglio print, but the
are most often combined with line etchings and softgrounds to add value and
richness to an image. If your plate has already been etched, it will still need
to be de-oxidized (Step 1 below).
Materials used:
• Airbrush (Badger model recommended)
• Compressor
• Hunt Speedball Water Soluble Screen Filler 4570
• 2 copper plates (1 will be a small test plate)
• materials for stencils (paper, X-acto knife, small coins or weights)
The Screen Filler may be diluted with water. The greater the
dilution, the finer the aquatint. The force of the compressor (PSI) may also
cause grain of the aquatint to vary. A dilution to start with is 70% Screen
Filler to 30% Water.
Procedure:
1. Remove all grease and oxidation from the plates (Dawn; Salt & Vinegar), and rinse with water. Dry the plates immediately, and cover their backs with contact paper to protect from the ferric chloride etch.
2. If there is any area you wish to preserve as bright white (or paper color) this is the time to stop it out with screen filler (or Future) on your plate.
3. Using the airbrush, apply the Hunt Speedball Screen Filler (appropriately diluted) to your image on the plate, and in equal amounts to a test plate. Remember that the screen filler is going to prevent the plate from etching: it is the minute areas of open plate between the droplets of screen filler that will etch and produce your tonalites. Therefore: more screen filler produces a lighter value than less screen filler. Use your Radio Shack magnifier to check for coverage, and aim for 50% coverage of the plate - in other words the areas between the drops of screen filler should be about the same size as the drops themselves.
4. Stencils may be used to block out areas you wish to preserve, whether they are sprayed or open. However, if you wish to keep some areas white you will need to cover those areas completely with screen filler before etching the plate. Try using a litho crayon if you want a softer effect or a crayon-like white line.
5. Screen Filler dries quickly and will clog the airbrush. If you are not actively spraying, the airbrush should be submerged in an ammonia/water solution.
After you have finished, it needs to be cleaned out thoroughly and carefully.
If this is not done it causes problems for everyone in the studio who wants to create an aquatint.
6. Etch the test plate, stopping out at stepped time intervals. The shorter the etch, the lighter the value of the final tone. The longer the etch, the darker the value.** The strength of the etchant will vary, so until you are experienced enough to judge the appearance of the printed plate by examining the depth of the bite under a magnifying glass, this is an important step. Use screen filler applied with a brush to stop out the action of the etch as follows:i. remove plate from ferric chloride
ii. rinse THOROUGHLY with water
iii. Immerse in deoxidizing solution (salt & vinegar) for several minutes
iv. rinse off salt and vinegar with water
v. dry plate wioth hair dryer
vi. apply screen filler with a brush to stop action of ferric chloride on specific
areas of your image
vii. dry plate (hair dreyer) and re-etch. Repeat entire process (steps i - vii) as
many times as is necessary.
7. Remove the screen filler from the test plate with an ammonia & water solution and proof it. Label the proof according to the total time each area has been in the etchant. Proceed to etch the image on your other plate according to the times in the ferric chloride as necessary for each appropriate value. Take the plate out of the ferric chloride and stop out areas as they have been etched for the right amount of time. (You'll need to rinse off the plate, dry it, apply screen filler with a brush and let that dry too before etching each step further).
**Once you are skilled with the airbrush you may be able to create an image which only requires a single time in the etchant by varying value with the flow of screen filler from the airbrush onto the plate. Obviously, it is helpful to know how to use an airbrush to use this technique. This does take practice. Use water soluble ink and create images in your sketchbook for practice before you start on a plate.
Special Effects:
If you have a taste for the unexpected:
• Dissolve some of the sprayed screen filler with water when wet, or a water/ammonia solution when dry.
• Use the litho crayon for stopping out over the sprayed screen filler. It gives the plate a nice tooth to draw on.
• Draw on a copper plate with a wax crayon. Coat it with future. When the future is dry, run the plate under hot water and rub at the crayon until it lifts the future up. Then spray with screen filler for a "lift ground" effect (strong black crayon-like marks).
• Experiment with other techniques and materials in combination with this process and share the results with the class.
See your textbook for other possible uses of this method.