Do you need a vector or raster image for your project? Learn about the features of vector file formats and how they differ from raster files with this in-depth guide.
Cover image via Kit8.net.
Whether you know nothing about design or you’re just getting started in the industry, you might struggle to figure out which file format you need for your project. Luckily, there are only two image file types you really need to know about: raster files and vector files. A raster file is made up of square-shaped pixels, like a photo taken on a digital camera. A vector file is a graphic based on mathematical curves and paths instead of pixels, like a company logo made in digital illustration software.
The most important thing about vector files is that they’re resolution independent, meaning you can make them bigger or smaller without hurting the quality of the image. In fact, vector files can do lots of things that raster files can’t, making them essential for many creative projects.
What is a Vector File?
A vector file is a computer graphic that uses mathematical formulas to render its image, instead of using pixel data like a raster file.
A vector image begins with a point. Two points create a path. Paths can be straight or curved, and then connected with more points to form longer paths or closed shapes. Each path, curve, or shape has its own formula, so they can be sized up or down and the formulas will maintain the crispness and sharp qualities of each path. This makes vector files ideal for displaying graphics at minuscule or considerable sizes.
Image via Tasiania.
There are a few advantages to using vector files:
- Scalability – No matter how big or small you make a vector, it will always look as sharp as the original. Check out the zoomed-in portion of the tropical pattern above.
- Small file size – Vectors use paths instead of pixels, so the file sizes are much smaller than their pixelated counterparts.
- Easily editable – A vector file lets you manipulate its colors, shapes, sizes, layout and more.
The only downside of vector files is their compatibility; you must open them in a vector-based design program such as Adobe Illustrator or Sketch. Raster-based programs such as Adobe Photoshop will only rasterize the vector files, eliminating your ability to quickly edit the graphics.
When Should I Use Vector Files?
You should use vector files whenever you need graphics displayed at various sizes. Think of a company logo. This logo will appear on business cards, brochures, and flyers. But it might also appear on T-shirts, billboards, and tiny mobile device screens. Other common vector files include icons, typography and lettering designs, patterns, and digital illustrations.
Vector files might sound a bit complicated, but you don’t have to make them yourself! You can find tons of stock vector images on Shutterstock, including fonts, patterns, icons, and illustrations that are all ready to customize. We even have a curated bundle of vectors for small business to help get you started.
What is a Raster File?
A raster, or bitmap, file is a computer graphic made up of many square-shaped pixels that denote the shape and color of each point in the image. These pixels are the building blocks of every image or design you see online. Just zoom in on an image to see those pixels become more apparent.
Image via Tasiania.
Most raster images appear crisp when zoomed out, but when zoomed in the pixels become more obvious, like in the tropical pattern above. Raster files are resolution dependent, meaning the image displays properly at a certain dimension and anything bigger will stretch the pixels and make it blurry. They usually comes as JPG or PNG files — learn more about PNG vs JPG to figure out which is right for you.
When you download raster files online, pay attention to file size and quality. Higher resolution images feature millions of pixels. For example, the tropical pattern above is 4000 x 4000 pixels, meaning there are 16 million pixels present in the image. Typically, the more pixels present in an image, the larger the file size and the better the quality. You can always find high-quality, high-resolution images on Shutterstock.
When to Use Raster Files
Raster files are best used for highly detailed photography or digital applications. The pixels seen in raster images allow for smooth color variation and crisp details in a high resolution graphic. Raster-based design programs such as Adobe Photoshop or Shutterstock Editor let you manipulate individual pixels. When you use raster graphics in your design work, always be sure to only scale the image down to prevent heavy pixelation.
Common Vector File Formats
Vector files can be saved, accessed, and exported in four main formats – AI, EPS, SVG, and PDF. Each format has distinct features and qualities that affect how it can be transmitted or read across programs.
Image via filborg.
An AI, or Adobe Illustrator Artwork file, is proprietary to Illustrator and can typically be read and edited within its native program, with some exceptions. In addition to Illustrator, CorelDRAW can also edit this file format, but with limitations. These files are also version-dependent, meaning the same file will be viewed differently across distinct versions of Illustrator.
An Encapsulated PostScript file features two-dimensional vector graphics, text, and bitmap imagery. This file format is a standard way of exporting vector designs because it can easily be transmitted between design programs and users without data loss.
When you download a stock vector image on Shutterstock, you will notice it’s exported as an EPS file. You can open this vector file format in Adobe Illustrator to edit, or turned into a raster file in Adobe Photoshop.
An SVG, or Scalable Vector Graphic, is a text-based description of images consisting of vectors, raster imagery, and text. It’s resolution independent and it displays high quality at lower file sizes, making it ideal for the web.
A PDF, or Portable Document Format, is a universal standard file format that can display both vector and raster graphics. Use this file format for preparing a design for print or for displaying your vector graphics on the web.
Interested in more design fundamentals? Look into these informative articles:
- 5 Essential Techniques for Drawing With the Pen Tool in Illustrator
- Process Color vs. Spot Color: What You Need to Know
- Revealing the Secrets of the Shapes Tool in Illustrator
- RGB vs. CMYK: Deciphering Color Modes for Print and Digital Design
- PPI vs. DPI: Demystifying the World of Online and Print Resolution