A common problem we encounter when working with clients is that many do not understand the specifics of the different types of File Formats. We will examine various types of formats, their uses and applications.
Raster, or bitmap images, are pixel-based images that are depicted as a grid of microscopic picture elements known as pixels. The raster image can be photo-realistic and is most often used for digital photographs, including digital camera photos and scans. Raster images are resolution-dependant, so the size and quality of the raster image is directly linked to the number of pixels in the file. Thus, changing the size of the file affects its resolution. Resolution of raster images is generally depicted by the number of pixels per square inch contained in the file. The proper resolution is dependent on the use of the image and the scale to be used.
Vector graphics are based on mathematical descriptions of points, lines, and curves, like a connect-the-dots puzzle. Vector images are resolution independent. They have no resolution until printed. Images can be scaled to any size without losing quality. The file sizes of vector graphics are usually much smaller than raster (or bitmapped) images.
Figure Above: A circle is shown as a vector (left) and BMP (right) graphic with too-low resolution. Vector graphics are infinitely scalable and have small file size, but are not photo-realistic.
Standard file formats for vector graphics include EPS (encapsulated PostScript) and PDF. and our preferred format, Adobe Illustrator (.AI).
Standard file formats for bitmap/raster graphics include TIFF, EPS, PDF, JPEG, Camera Raw and numerous other formats for Web graphics, such as GIF and PNG. Adobe Photoshop and their competitors can read all of these formats, and page layout programs can place these formats.
Obviously, we prefer to get art which is in a Vector format, especially for logo’s. If you are providing art as a raster/bitmap, just remember that we can not make it much larger then the resolution of the image you provide us.
If you have questions or comments, please feel free to post them below!