Raster vs. Vector Images – A Quick Reference

By Yvette Fitch

vectorraster

 

When submitting artwork for a print order, your graphic designer may ask you for Raster or Vector graphics.  Knowing the difference can save you tons of time in back and forth with your design team.

Here’s a quick reference to help you decide which of these two image types are best for your artwork.

Raster Graphics

Raster graphics are made up of tiny colored squares, which  are called pixels or dots.  The amount of squares determines how much color detail is in the image.  If your image has, for example, 72 dpi, this means the image contains 72 dots or pixels of colored squares in each square inch.  300 dpi graphics contain 300 squares, and so on.

The higher the dpi of the image, the higher the quality (and file size).

dotted cat_10

Raster Cat – Enlarged to show dots / pixels

When it’s best:

Raster graphics are most commonly used with photographs or graphics, where color shading and detail is important.  Each dot’s color can be edited individually, making it possible to add realistic dimension.

Why it might not work:

Raster graphics tend to become blurry (or pixelated, ie. the individual dots become visible) when you enlarge them.  It’s very important to supply your print house with graphics with the highest dpi and as close to the final image size as possible.

Common image file extensions: .png, .jpeg, .gif, .bmp, .tiff

 

Vector Graphics

Vector Cat – Exaggerated polygons NOT typical

Vector graphics are created using geometric items, like points, lines, curves, and shapes, unlike raster graphics, which are composed of individual dots of color.  The outline of the shapes are determined and filled in mathematically by a computer to create the final image.  Vector graphics are entirely computer-generated artwork.

When it’s best:

Vector graphics are ideal for items that my need to be enlarged without losing the crispness of the edges and details. This makes them ideal for corporate logos, and web graphics that will need to be manipulated.

Why it might not work:

One downside to vector graphics is the lack of photo-realism of the graphics.  They do tend to look flat and cartoonish, compared to what is possible with raster graphics.

Common image file extensions: .eps, .ai, .svg

In a nutshell:  if you’re looking for graphics, like a photograph, then raster graphics will give you that realistic look you require.  However, if you’re looking for graphics that can be resized without lost of detail or clarity, vector graphics are the way to go.

 

Leave a Reply