There are 2 main types of graphic files.
First, there is a photograph.
These are known as Raster Files.
A raster file (such as a jpg, gif, tif, .png, etc.) is resolution based and perfectly fine for print given that the resolution is high enough. A good rule of thumb is: the resolution should be about 100-200 dpi (dots per inch) at the actual size you would want printed.
That doesn't mean that you can take a 72 dpi image, resize it, then re-sample it to 100 dpi. Resampling is a computer process where the closest pixels are interpolated to generate a filling pixel in the space created by enlarging a photo. This leads to blur and artifacts in your picture and is not recommended for print.
The second type of graphic file is Vector Files.
A vector file (such as an .eps, .svg, .pdf, etc.) is not based on resolution, but mathematical relationships between points with color values applied to closed shapes and strokes. These files can be resized to ANY size without loss of quality because there is no interpolation.
For certain purposes, a vector file can be turned into a photo, but it is more difficult and sometimes impossible to vectorize a photo. For example, a 1 color logo on a business card can be scanned at 300 dpi, blown up 3 times it's original size (making it 100dpi) and printed fine. But that same 1 color logo, can be vectorized or traced and blown up to ANY size. The problem is, if a file has many colors or is a photograph, the vectorizing process becomes too complicated and too cost restrictive to be practical. So, photographs are limited to resolution as to how large they can be printed.
One thing to be weary of is a file that contains both Raster and Vector Graphics. SVG, EPS, PDF, and AI files can all be saved with embeded rastor graphics. The final size of the print should not push these embeded graphics outside of the 100 dpi realm or these images will be blurry/distorted and not satisfactory by any means.
If you have a question about any file you have that you would like reproduced, please send it to us or give us a call and we will happily help you.
