Preparing images to print can be a tedious task. Reducing image size won’t cause a problem because you’re only removing unnecessary pixels. Increasing image size can be a nightmare. To make an image larger, computer software has to create new pixels based on an analysis of the original image. Even with all the advances in modern imaging software, this process still creates artifacts (noticeable imperfections produced by a digital process). Higher end programs minimize this effect but it’s still not perfect. There are two options to overcome this issue:
1. Design your images as vectors. Vector graphics are images rendered through the use of mathematics. Instead of storing the actual image, a vector file stores a set of instructions on how to recreate the image. The benefit of this format is the ability to be enlarged without artifacts. Instead of creating new pixels, the calculations stored in the file simply adjust for the larger size. Other benefits include small file sizes and the ability to easily edit the image at any time.
2. Bitmap (raster) graphics are based on a grid of pixels which are square points on the screen that comprise the images we see on the screen. The bitmap file stores the information for each pixel within the image so the file sizes for larger images can take up a lot of space. The reason we rely so heavily on bitmaps is that they can actually display life-like images. Bitmaps do not rely on mathematical equations so they can replicate the intricate lines and colors that are too complex for vectors to calculate.
Despite the difficulty of enlarging bitmap graphics, they can accomplish details that vector graphics cannot. Bitmap files can store much more detailed information such as the vivid color patterns found in nature.
Vector graphics can’t replicate the complicated tones and arrangements that make images look “real-life”. Vectors graphics are best suited to less detailed designs, they work very well for logos and stylistic renderings.
Knowing the differences between the two formats will make it much easier to ensure that you get excellent prints.