Date: January 23, 2014 Researcher’s Name: Cathe Janke
Room Temperature: 65 degrees Farenheit, dry
Still testing the possibilities of using an extreme black and white image. The purpose of this test was to follow the original directions using a drawing that has a black background and a white drawing as the foreground, to determine how the PCB film responds with an image being created by white lines.
1. Kept image as a jpeg. (original file form, imported from camera)
2. Image > size> 5.667, 4.25, 300 dpi
3. Layer> New Adjust Layer> Invert
4. Layer> New Adjust Layer> Color Balance Highlights- Cyan= -31 Magenta= 0 Yellow= -26
5. Layer> New Adjust Layer> Channel Mixer > monochrome
6. Layer> New Adjust Layer> Curves, 4 points (see graph)
A: O: 45 I: 0 B: 0:62 I: 64 C: 0:171 I: 175 D: 0: 225 I:255
7. Filter> Filter gallery > preset aquatint screen, 720 dpi
8. Print, same as original directions, except, dpi on printer at 300 dpi.
Print Parameters Used Let Photoshop determine colors. Gray Gamma 2.2. Rendering intent=Perceptual. Presets= Plain Paper, Resolution HQ 300
Plate Material: .032 Copper Plate Size: 4.25″ x 5.75”
The plates were beveled, polished with 00 grade steel wool, and degreased with soy sauce and bon ami.
The image was printed on the PCB film with a Brother HL2280DW laser printer. The copper plate was placed on a phone book and the film was placed on its surface print-side-down. The film was carefully heated to the plate with a tacking iron for 8 minutes at 300 degrees F.
Testers found that backing the plate with contact paper was most pragmatic AFTER the plate had been ironed and cooled and with the film still adhered to the plate.
Etching Notes: The plate was etched in a 39 degrees Baume Ferric Chloride bath in a vertical tank.
Time in Bath: 20 minutes
Removal of Grounds: Plates were saturated with SoySolvII cleaner and left to soak for 5 minutes. Ground was then wiped off easily with a rag.
After Bath Evaluation: Looks like a good transfer and an interesting plate.
Inking Methods: Plate was inked with Graphic Chemical Etching Ink in Bone Black, applied with a piece of mat board. It was gently wiped in an outwards motion with a piece of tarlatan. Then paper wiped, then hand-wiped.
Paper Type: Hahnemuhle, warm white Paper Soaking Time: 30 minutes Press Blanket Setup: Takach pressure at 5.5, 2 blankets, sheet of newsprint
The image came out well and the tester was able to see the grain on the plate and notice that the laser printer was creating a pattern as strong or stronger than the aquatint screen being embedded in Photoshop.