For this trial, we brought in a fourth party to add insight to our Photoshop process. As with the previous test, all alterations made in this experiment pertain solely to Photoshop adjustments. Once again, two plates encompass this trial. Both plates have the exact same Photoshop adjustments. However, both plates were assigned different profiles to be read by the printer, explained under Plate “Preparation.”
Date: April 30, 2013
Researcher’s Name: Liz Bannish and Stephanie Gaumond
Plate Material: Copper 0.032″
Plate Size: 6″x6″
Room Temperature: 70° F
Plate was backed with contact paper, beveled, polished with 00 gauge steel wool, and degreased with a ratio of 1:1 soy sauce to water.
Image was opened in Photoshop. The channel mixer was opened under Image>Adjustments>Channel Mixer. In the Channel Mixer menu the “Monochrome” box was checked to give the image an appearance of black and white, even though it was technically still being profiled as RGB. In the Channel Mixer the sliders were adjusted to bring all values in the image just about down to a middle gray. Red: +74, Green:+18, Blue:+2.
A new adjustment layer was added and the shadows, midtones, and highlights were adjusted under Image>Adjustments>Color Balance.
Image was made Grayscale under Image>Mode>Grayscale.
Finally, a new adjustment layer was added and under Image>Adjustments>Levels, blacks were pushed to 73 and whites were placed at 197.
The image was ready to print. As mentioned above, we placed different print parameters for the two plates to see if, additionally to the new Photoshop settings, a certain print profile was best suited for the image dot pattern.
The following settings were applied to both Images: under Image Size had the “resample image” box unchecked, resolution set at 300 ppi, and in the Print Preview dialoge box under “Print Profile” Gray Gamma 2 was selected. Color handling set at “Let Photoshop determine colors” and Rendering Intent set at Perceptual.
Plate A: Under “Print Settings” the media type was set at “Plain Paper” and Print Resolution set at 600 dpi.
Plate B: Under “Print Settings” the media type was set at “Plain Paper” and Print Resolution set at HQ 1200.
Both images were ironed with a tacking iron at 300 degrees F for 8 minutes.
Soon both testers realized that they had made a grave mistake.
Both plates were etched in a 40 degrees Baume Ferric Chloride bath.
Timed Application of Mordant
30 minutes in a vertical tank
Removal of Grounds
Grounds were removed with a 00 gauge steel wool pad.
After Bath Evaluation
Unfortunately, it was after the image was etched when we realized that the image was never inverted! This means that it was never converted to a negative, thus our image would be backwards anyway. In any case, the image was printed as usual since the value ranges, in essence, would still be able to be read correctly.
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.
Paper Type: Hahnemuhle Copperplate
Paper Soaking Time: 10 Minutes
Press Blanket Setup:Takach pressure at 5.5, 2 blankets, sheet of newsprint
It appears that neglecting to invert the image did have greater effects than the values just reading “backward.” The dot pattern placed by the printer without the image being inverted meant that the image as a whole etched very dark. As in previous prints, diagonal lines are present where the dot pattern remained too closed to accept the etch. A lower dpi appears to be more successful, as the HQ 1200 (Plate A) resulted in an image too closed off to accept the etch at all.