TIFF, JPEG & PNG (Rasterized Artwork)

Artwork saved as a TIFF, JPEG, or PNG file is stored in a raster format.  Artwork created in a raster format is resolution dependent, meaning that it will not enlarge successfully; therefore, you will have to create the artwork at the final output size, with enough resolution to print at 300 dots per inch (dpi).  What does this mean for your artwork?

Let's take an example: suppose you are laying out your artwork for a business card.  Although the size of the printed card will be 3.5" x 2", the print margin of the card will be only 3.25" x 1.75". In order for the card to print at 300 dpi, the width of the image you are creating needs to be 975 pixels (300 dots per inch x 3.25 inches). The height would need to be 525 pixels (300 dpi x 1.75").

When this file is uploaded, it will fit perfectly within the print margins of the business card at the proper 300 dpi resolution.

To understand what would happen with less than 300 dpi, suppose your artwork was only 500 pixels by about 270 pixels.  Trying to "spread" 500 pixels across 3.25 inches leaves only about 150 pixels for each inch on the card, resulting in poor print quality (similar to the graininess seen when enlarging a photo).

In order to avoid having any resizing performed on your raster artwork, it is important to remember that if the artwork is less than the size of the product's print margin (at 300 dpi), then it needs to be "bordered" with white space to meet that size.  Click here for an example.

 

EPS (Vector-based Artwork)

EPS (Encapsulated PostScript) files are documents which contain PostScript commands that tell a printer precisely how to draw the image.  This causes EPS files to be resolution independent.  When resized, the printer correctly draws the same images to the new size, retaining the quality.  However, if a raster file (i.e. TIFF, JPEG, etc.) has been embedded within the EPS file, it will have the same limitations with resolution as described above.  Click here for an example.

If your EPS file is not exactly the same size as the product's print margins, it will be rescaled to fit these margins.  Therefore, when laying out your artwork from a program like Adobe Illustrator, it may be necessary to place an invisible border around the artwork to ensure that the artwork is exported with the correct margin size. Otherwise, the artwork will be clipped to the size of the EPS file's "Bounding Box", which is the actual size of the artwork within the file. Click here for an example.