Studio Practice : Digital Preparation of Positives for Screen Printing

Digital Preparation of Positives for Screen Printing

Using Photoshop & Illustrator

Scanner Software - Image Capture

Default scan at 300ppi

Choose an image

Step 1

Image Adjustments Click "Desaturate" - to remove all colour from the image

Step 2

Change the contrast to a high contrast image using the half circle in layer options

Step 3

Adjust the Levels - use the black and white slider ( both sliders on top of another creates the greatest contrast)

Step 4

Click the half circle layer option and select "Threshold" - this removes all greys from the image making the image consist of only black and white pixels.

Step 5

Use the polygon lasso tool, press "g" change the tool from gradient to paint bucket and fill the shape in black

Step 6

Check the colourise the layer, hold alt and click the line joining two layers - this enables you to only change the hue and saturation of that particular layer.

Step 7

Turn off "Hue and Saturation" before you print the digital positive

Step 8

Alter layer blending mode from "Normal" to "Multiply"

Step 9

Consider "overprinting or knocking out" Knocking out involves removing an ink from underneath to do this use very simple selection tools

Step 10

Use the magic wand tool and delete a section

Step 11

Then select the background layer and set the layer mode to "Multiply"

Step 12

Consider "Registration" - this is a consideration for printing ink

Step 13

Choose third image and change the mode to "Multiply" - removing the white background

Step 14

Half tone - allows us to print different tones of one ink - using a half tone screen by using dots varying in size creating the illusion of tone

Step 15
Normally again adjust the levels then "Select All" then "Edit" "Copy Merged"

Step 16
You must use illustrator to print, Open Adobe Illustrator select "File and New"

Step 17
Make sure the black and white printer is selected

Step 18
Look at the "Output" option on the printer menu change mode from "Composite" to "Separations (Host-Based)"

Step 19
Alter the "Frequency" - half tone dots in every inch "50" is the maximum always keep the same frequency, "10" will show dots for aesthetic use

Step 20
The "Angle" should be set to 15 each screen should have a different angle

Step 21
You can alter the dot shape to dot or line to create a different aesthetic