Vector vs. Raster

In the printing industry I find myself asking for vector files on a regular basis. Over the course of many years I have discovered that most people outside the graphic design world have little to no idea of what I am asking for or simply do not have access to that type of file.

While there are many outlets out there for logo creation and graphic design services, being educated on what you may or may not need beyond the logo is essential to your marketing and advertising. Securing a knowledgeable and skilled graphic designer that you can communicate directly with can also prove important in communicating needs which brings us back to the topic of the article, vector files versus rasterized files. I'll break down each one below.

Vector files: Useful in many different environments.

When you’re working digitally, there are two kinds of image file types: raster and vector. Both image types may be saved with several different file extensions. It’s important to understand when to use each image type and the best file extension for particular situations.

Vector files are images that are built by mathematical formulas that establish points on a grid. Vector files are more versatile for certain types of tasks than raster files. The most common types of vector files are:

ai: Short for Adobe Illustrator, this file is commonly used in print media and digital graphics, such as logos.

.eps: Encapsulated PostScript is an older type of vector graphics file. .eps files don’t support transparency in the way more modern file formats like .ai do.

.pdf: The Portable Document Format is built for the exchange of documents across platforms and is editable in Adobe Acrobat.

.svg: The Scalable Vector Graphics format is based in XML (a markup language used widely across the Internet that's readable by both machines and humans). It’s useful for the web, where it can be indexed, searched, and scripted.

Since vectors are based around formulas, a vector image can scale at high resolution to virtually unlimited sizes. If you have a business logo saved in a vector format, it can be resized to fit on a billboard with no problems or reduced to be printed on a ballpoint pen or business card. Many printing processes can only work with vector file input.

Raster Images

If you surf the web, chances are you have seen a raster image. Raster, or bitmap, images consist of tiny squares called pixels. These pixels contain bits of color and when combined, they build images. The more pixels in an image the higher the quality, and vice versa. When you zoom in on an image the pixels become more apparent while the details of the image become blurry.

Raster images are used in photography and digital applications. When you take a picture with a phone or a camera the image is recorded as pixel data, and when these images are uploaded online the end result is a raster image. To edit these images you need access to raster-based programs like Adobe Photoshop. For design work, it is best to use these programs for photography and imagery only; avoid using them to design logos and icons. Raster files are saved in various formats:

.tiff (Tagged Image File Format)

.psd (Adobe Photoshop Document)

.pdf (Portable Document Format)

.jpg (Joint Photographics Expert Group)

.png (Portable Network Graphic)

.gif (Graphics Interchange Format)

.bmp (Bitmap Image File)

While all of these display pixels, each file format has its own distinct display settings. Some files take up additional data and use higher resolutions, while others take up less storage but tend to be lower in resolution and quality.

You'll notice a few underlined and emphasized points above. These points of emphasis and the file extensions noted above can help you become more educated as to what type of file you need for a given application and why it is important to have and utilize both types. Trust me, both your printer and your web designer will thank you (and me) for it. Before hiring a graphic designer or using an online design service (bad idea) ask what types of files you will recieve upon completion of the contracted work and if you don't hear any of the terms above, or are not getting both types of files, take caution in proceeding.

Contact me with questions, if you need tips, or even for graphic design projects!