I will use this page to describe some solutions to problems that may occur when you work with backgrounds in your PDF files.
Quality and Colors
Sometimes it happens that the PDF you are trying to use as a background isn't very compatible with the built in way of handling it. The result can be that the background is of poor quality. Images may be rasterized and colors may be slightly different compared to the original background PDF file.
Why is that? Well, your PDF can contain two types of information:
- Bitmap graphics.
- Vector graphics.
Bitmap graphics does not scale very well. Vector graphics on the other hand, scales very well. The best results when printing on a background PDF are produced when the background PDF is based on vectors.
If you just make a scan of an existing paper with a letterhead, then you get a large bitmap instead of a vector based background.
Typically, the best background PDF documents are created by your professional designer if you ask them to produce a PDF with your letterhead where both text and graphics are based on vectors.