Offset Printing: A Comprehensive Guide
Offset printing is a type of printing process that uses plates to transfer images onto the final printing surface, such as paper or textiles. A plate is a flat, relatively costly object that can be reused multiple times, though its quality deteriorates with repeated use due to wear and tear. This wear shows in the final product as spots and scratches. Offset printing allows for printing on large rolls of paper with minimal loss of image quality.
Traditionally, offset printing is used for large print runs as it is more efficient than other methods, particularly for colour reproduction. It also requires less setup time compared to alternative techniques. Offset printing is generally available in CMYK (four-colour process), as it uses four plates—one for each colour (cyan, magenta, yellow, and black). It is also commonly used for posters and other large-format graphics due to its ability to produce high volumes at a reasonable cost.
Offset printing has been around since the 1900s and has changed little over the years, aside from improvements in quality and efficiency. It remains a popular method today due to its cost-effectiveness compared to other printing techniques.
What is the CMYK Colour Model or Four-Colour Process?
CMYK is a colour model used in colour printing. It is a subtractive colour model, meaning it is based on the combination of cyan, magenta, yellow, and black inks.
The CMYK colour model can be used to print photographs or artwork in full colour. It relies on cyan, magenta, yellow, and black ink to produce all visible colours on the printed piece.
CMYK is also referred to as the four-colour process because it involves the use of four separate colour plates to print an image. This differs from RGB (red/green/blue) printing, which uses a single plate. When creating an image in RGB mode on a computer, your screen displays only three colours (red, green, blue). To ensure the image appears as intended on paper, it must be converted from RGB to CMYK mode before being sent to the printer.
Why Should Communication Agencies Understand CMYK?
Offset printing is widely used for newspapers, magazines, and books because it produces high-quality images with sharp details and vibrant colours, making content easy to read, even for those with visual impairments. Offset printing is also well-suited for large-volume projects as it does not require expensive equipment.
