Artwork 101 (Part 1): Rascally Rasters & Vectors
One of the most challenging aspects of running a print & sign business is helping our customers provide suitable artwork that will result in beautiful prints. For all of the benefits of Artificial Intelligence (AI), acquiring high quality artwork doesn’t seem to be one. Many customers rely on AI these days to easily create company logos, but they don’t realize that the AI artwork is rarely high enough resolution to produce quality prints. There is also the underlying issue of whether or not the customer has the legal licensing to use the AI created logo commercially, but that is a different topic for a different article.
Raster Versus Vector
There are so many avenues we could follow related to this topic, but let’s start with the basics. For our purposes, there are two types of digital images: raster and vector. Raster images are composed of thousands of pixels (tiny squares or dots) that, when brought together, can accurately represent a picture. Raster file formats include JPG, PNG, GIF, TIFF, and BMP. The quality of a raster image depends on the resolution, the number of pixels or dots per square inch (dpi = dots per inch). The higher the dpi the better the image quality. One thing that is very important to understand is that the dpi of a raster image changes when the image is resized. When a raster image is enlarged, the dpi decreases which degrades the image quality. This low resolution can make the image look blocky, fuzzy, and unclear, especially when printed. This degradation of image quality is referred to as pixelation. Conversely, the dpi of a raster image increases when the image is made smaller, improving the image quality. Therefore, most issues with raster images occur when the image needs to be enlarged for printing. The key to using raster images is making sure the resolution (dpi) is sufficient at the size needed for printing. Ideally, images should be 300 dpi at the print size to ensure high quality printing. The image size and appropriate dpi must be set at the beginning of the design process before the image is created.
Vector images are created using lines instead of pixels. These lines are connected by points or nodes (like a connect the dots drawing). When the line connects back to itself, the path is completed or closed and a shape is created. This shape is filled with a selected color. A vector image is typically made up of multiple paths/shapes, each of a different color that combine to represent the desired image. Vector file formats include SVG, EPS, PDF, AI (Adobe Illustrator), and CDR (CorelDraw). Not all images can be accurately represented in vector format, and for that reason raster images are often needed for detailed image reproduction. However, when suitable, vector images have a distinct advantage over raster images in that they can be infinitely resized without any loss of image quality. For this reason, vector images are a great option for company logos which may need to be used for a variety of purposes and in varying sizes.
There are programs that can perform a vector trace, converting images from raster to vector. However, the quality of the trace depends on the quality of the original image, and oftentimes the traced vector will demonstrate inaccurate line reproduction and unwanted artifacts. For that reason, best results can be achieved by having a trained graphic artist redraw the image by hand using a program such as CorelDraw or Adobe Illustrator. If a redraw is necessary, we at the Vinyl Motif have the tools and experience to complete this process for you with great results at an affordable price. When complete, you will receive the artwork in multiple formats that can be used for a variety of projects.
