ImagesMagUK_December_2021

www.images-magazine.com 26 images DECEMBER 2021 Industry experts provide insight and guidance in all areas of digital garment and textile printing Digital helpdesk Margareta Fuchs and Everson Scheurich of DTG Merch discuss how vectorising graphic files works, which designs for DTG printing can be ‘rescued’, and when to use automatic vectorisation processes [L-R] Everson Scheurich and Margareta Fuchs mathematical calculations between two points that form shapes and lines. When you zoom in on a vector graphic, it always looks sharp. They can also be enlarged without losing quality. The good news is that many images can be created using both methods and still look the same. And those are the ones you can ‘recover’ and turn into printable designs if the quality is too low. This is where vectorisation comes in: you convert a raster image into a vector file, usually by tracing the design – either automatically or manually. Which designs can be used? The designs that can be easily vectorised are the classic screen printing designs that have clean lines and only a few solid colours. It is also possible to create vectors for more complicated designs (although automatic tracing does have its limits). A typical case is logos: clients regularly provide their logos in poor quality and small file sizes, and do not have them available in better quality. The file is too small for DTG printing and would result in a poor print quality, especially if it had O ne challenge with direct-to- garment (DTG) printing is that it requires designs in large sizes and high resolution, especially if you want to print large designs that go across the entire front (or back) of a T-shirt. It regularly happens that the artwork is not up to it and the designs have to be scaled or resized, resulting in inferior prints – or that they have to be printed in a much smaller format to look decent. Neither of these is usually in the client’s best interest. Depending on the design, there may be a way to make non-printable raster images suitable for printing with DTG: vectorisation. What is vectorisation? When we mention vectorisation, we often get confused looks because one of the ‘credos’ is that vector files are typically used for screen printing and raster designs for DTG. The beauty of DTG, however, is that it can usually print both file types, depending on the specifications of your RIP software. And even in the rare case that your RIP is not able to do this, vector files can simply be rasterised again in a larger format without loss of quality in order to make them printable. The difference between the two main types of image files, vector and raster, is briefly this: raster images consist of a certain number of pixels. When you enlarge them, you increase the size of the pixels, which means you’re likely to see the individual small squares. And if you enlarge them even more, the design becomes blurry. Vectors, on the other hand, are the outlines of shapes, Low-quality files can be transformed by vectorisation