Simulated process color separations are created when you want to screen print a process color print onto a dark-colored shirt. Common images and clients for simulated process color prints include rock bands, fantasy groups, animals, motorcycles, and photographs. Process color simulations only work well on light-colored shirts. Creating a separation for a dark shirt is more complex.
Simulated process color differs from true process color because these images are not printed using CMYK inks like regular process prints. These images are printed using “regular” colors like red, black, orange, yellow, blue, white, etc., and are printed with all-purpose inks. For simulated process color prints, you also have to create extra plates including an underbase and highlight white.
Before performing any simulated process color separations, there are a few items that must be reviewed and checked. For instance, make sure after you perform the separations and output them that your printing department can successfully and accurately mix the inks, align the screens, have and use the correct equipment, and have enough stations on their presses to handle the job. If the printing department can’t meet these minimal requirements, the print won’t come out right at press time.
Additionally, check these items:
· Make sure the image you are working with is at least 150 dpi. Anything between 150 and 200 dpi is reasonable.
· Make sure the image is in RGB mode.
· Get the image as perfect as possible before separating it.
· Verify that the background in the image is the same color as the shirt. Black backgrounds work great on black shirts. However, if the background of the image is not the same color as the shirt, you’ll have to extract the image, place it on a new layer, and create a background layer that is the correct color.
· Verify that someone in your shop has experience with process color separations; if they don’t, consider purchasing videotapes, attending a class, or visiting another screen print shop for pointers.
Note: Although simulated process color is generally reserved for darker shirts, it can be used on lighter ones. However, regular process color is generally easier, so this process is normally not employed under those circumstances.
This information was excerpted from my book, Photoshop 7.0 for Screen Printers. A new version is available for CS3 at www.wordware.com. Use the code ps0365 for 35% off this book and any others at the site.