Color separation prepared for production.

Bob Marley — Six-color separation for a black T-shirt

Image construction with an optional white underbase

This study presents a six-color separation prepared exclusively for printing on black T-shirts. The image uses yellow, red and green as accent colors, together with light brown to build the skin tones and two white channels with different roles.

The aim was to prepare an image that could be printed in two ways: using a white underbase to support the colors, or printing directly onto the black fabric, provided that the inks have sufficient covering power.

The white underbase mainly provides support for the colors that follow. It was prepared with moderate coverage to avoid laying down an excessive white layer at the start of printing. Its role is to help preserve color intensity when the selected inks do not cover black adequately on their own.

The edges of this underbase also required careful control. Because the image contains fine lines and details, I applied a slight choke to keep white from showing around the colored areas if small registration variations occur during printing.

Another important consideration was the fit between colors. In certain areas, I slightly spread the yellow to improve its overlap with the red. This adjustment was also applied to the elements of the Bob Marley lettering, helping prevent small gaps between colors without compromising the definition of the design.

The highlight white was prepared separately from the underbase. It can strengthen light points, define volume and recover important image details. Its use is optional and can be adjusted to suit the intended result.

If the printer chooses to omit the white underbase, the color channels can be printed directly onto the black T-shirt using high-opacity inks. In that case, highlight white remains available to build the light areas and help define the image.

The PSD file allows each channel to be examined individually, the separation to be compared with the original image and the adjustments to be understood. The original reference was also retained in the file to make this comparison easier.

Although this is a relatively simple separation, the result depends on important decisions: control of the white underbase, registration between colors, ink coverage and the balance of highlights. These small adjustments help keep the image well defined without overloading the print.

Joel Mariano — PhotoshopSilkScreen

Print sequence · six screens

The Solidity values correspond to the settings shown on the study’s technical sheet, not to ink-mixing proportions.

Files for evaluation

The download includes the PSD with the complete separation, the original image in JPEG format and a reference image identifying the six channels. These files allow you to examine how the separation was built and compare the result with the original image.

This study complements the article Two ways to build a layered image in screen printing by demonstrating a separation that can be adapted for use with or without a white underbase.