press n peel test 23

press n peel test 23

Date: October 8, 2013

Room Temperature: 74 degrees Farenheit, dry

Researcher’s Name: Cathe Janke and Kristin Fitzpatrick

Test Summary: The purpose of this test was to determine the adjustments we needed to make in Photoshop. We made two separate images adjusted differently in Photoshop and compared the results.

The image to be used was opened in Photoshop, then inverted in two ways.

A.
Image> size > 300dpi
Image>Adjustments>Invert.
Image > Adjust> Color Balance: Highlights- Cyan= -31 Magenta= 0 Yellow= -26.
Image > Adjust> Channel Mixer: Monochrome box checked. Image> Adjust> Curves.
Curves: Black=45 White=225. Two middle points: Output 62/Input 64 (the gray-black) and Output 171/Input 175 (the gray-white).
Filter > Filter Gallery> Aquatint screen filter= 50%

B.
Image>size> 300 dpi.
Layer> New Adjust Layer> Invert.
Layer> New Adjust Layer> Color Balance Highlights- Cyan= -31 Magenta= 0 Yellow= -26.
Layer > New Adjust Layer> Curves
Curves: Black=45 White=225. Two middle points: Output 62/Input 64 (the gray-black) and Output 171/Input 175 (the gray-white).
Filter > Filter Gallery> Aquatint screen filter= 50%.

Both images were printed at the same time on one sheet of PCB film.
Print Parameters Used: Let Photoshop determine colors. Gray Gamma 2.2. Rendering intent=Perceptual. Presets= Plain Paper, Resolution HQ 1200

Plate Material: .032 Copper 
Plate Size: 4″ x 6”

Plate Preparation
: Two plates were used for this trial. 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 Press and Peel 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

test3aftertransfer

 

test3bfilm

Etching Notes: 
The plate was etched in a 39 degrees Baume Ferric Chloride bath in a vertical tank.
Time in Bath:  30 minutes
Removal of Grounds
: Plates were saturated with Soy Solv cleaner and left to soak for 5 minutes. Ground was then wiped off easily with a rag.
After Bath Evaluation
 :The plate etched effectively with no visible damage to the image quality.

test3.copper

Inking Methods: 
Plate was inked with Graphic Chemical Etching Ink in Bone Black, applied with a piece of mat board. It was gently hand-wiped in an outwards motion with a piece of tarletan. Then paper wiped.

Paper Type: Hahnemuhle, white
 Paper Soaking Time: 5 hours

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

t3_10_8proof

Test Conclusion: Some small differences were seen between the two images created in different ways in Photoshop. The top right corner of Plate A has a slight more gray tone in the image.

No noticeable difference between test #22 and this test. The mid-tones in the window area are washing out. 

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