press n peel test 29

Date: December 19, 2013

Room Temperature: 65 degrees Farenheit, dry

Researcher’s Name: Cathe Janke

Test Summary
The purpose of this test was to follow the original directions in test #17 using a drawing as the image to bring into Photoshop.  Changed point B in curves to input 62 and output to 107 and changed the printer to 300 dpi to see if any image can follow these directions, or if each image needs to be adjusted based on it’s own grayscale.


original drawing

Image Preparation in Photoshop
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: 3.5″ x 5.5”

Plate Preparation
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:  uneven transfer

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, white
 Paper Soaking Time: 10 minutes

Press Blanket Setup: Takach pressure at 5.5,  2 blankets, sheet of newsprint


Test Conclusion
Only open biting and shapes at the bottom of the plate appeared on the proof. Small part of the tail of the image showed up, but no mid-tones. Water may have been on the plate and small bubbles were not able to be removed with the iron. As the film was removed the toner pulled off the plate with film. It seems the same Photoshop curves settings cannot be followed for every image.

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