In order for the art department at FoodTent.com to effectively print custom canopy projects for customers, we request Vector based logos and text for most jobs. Unfortunately the discussion about logo format types throws most people over the edge. We hope this easy-to-understand article will help explain the difference between raster vs. vector files.
This image demonstrates the differences between a raster and vector , but you cannot always see the difference at a glance. When a raster image is scaled up, it usually loses quality. A raster image can be enlarged by either adding more pixels or enlarging the size of the pixel. Either way you are spreading the original data over a larger area at the risk of losing clarity.
A vector graphic uses math to draw shapes using points, lines and curves that can be scaled to any size without losing quality. Typically Adobe Illustrator is the preferred program for creating and editing Fonts and Logos. Popular vector file format extensions include: eps, ai and sometimes pdf.
Pros of Vector Images
- Infinitely Scalable: Through the wonders of math vector files can be scaled up or down as much as you want without losing any image quality. Whereas a raster image must guess the colors of missing pixels when sizing up, a vector image simply uses the original mathematic equation to create a consistent shape every time.
Cons of Vector Images
- Limited Details: Because of the mathematically way that a vector remembers data, they are not practical for complex images that require exact coloring. Sure, you can create basic color gradients, but you’ll never be able to match the color detail available in a raster image where each individual pixel can be its own individual shade.
- Limited Effects: By definition, vector graphics are created from simple points and lines. This means they can’t handle certain styling effects, like blurring or a drop shadow, that are available with raster images.
A raster graphic is an image made of hundreds or thousands of tiny squares of color information, referred to as either pixels or dots. The most common type of raster graphic is a photograph. The preferred program for creating and editing raster files is Adobe Photoshop. Popular raster file format extensions include: jpg/jpeg, psd, png, tiff, bmp and gif.
Pros of Raster Images
- Rich Detail: Ever wondered what the term “dpi” stands for? It means “dots per inch,” a measurement of how much detailed color information a raster image contains. Say you’ve got a 1” x 1” square image at 300 dpi—that’s 300 individual squares of color that provide precise shading and detail in your photograph. The more dpi your image contains, the more subtle details will be noticeable.
- Precise Editing: All of those individual pixels of color information can also be modified, one by one. So if you’re a true perfectionist, the level of editing and customization available in a raster image is almost limitless.
Cons of Raster Images
- Blurry When Enlarged: The biggest downfall to raster images is that they become pixelated (aka grainy) when enlarged. Why is this? Well, there are a finite number of pixels in all raster images; when you enlarge a photo, the computer takes its best guess as to what specific colors should fill in the gaps. This interpolation of data causes the image to appear blurry since the computer has no way of knowing the exact shade of colors that should be inserted.
- Large File Size: Remember how a 1” x 1” square at 300 dpi will have 300 individual points of color information for the computer to remember? Well let’s say you have an 18” x 24” photo— that’s 129,600 bits o’ info for a computer to process which can quickly slow down even the faster machine.
Raster or Vector Graphic Program for Design?
It depends on the design itself. If it’s going to have photographic elements with continuous tones and blends of color, you are probably better off using a paint program like Photoshop which is a raster program that specializes in photo editing, or use any other PAINT program.
If you want your final design to look like an illustration instead with clear contrasts between objects & shapes, then use a vector program.
Ideally a company that has a logo design with photographic elements, also has a secondary version of their logo in vector format that can be used for those specialty items that require vector art.