What is PDF/Acrobat?
Pdf is a postscript based format used for document exchange. It is widely used in the printing and graphics industries because it is usually very reliable and has many built in features that are either print aware or print specific.

How are PDF files produced?
Various methods are available. Many programs have a direct pdf export option - some of which are at present not suitable for generating pdfs for print. Creating a pdf that is suitable for viewing on your monitor is NOT the same as creating a pdf that is suitable for print.
Probably the best way to check if you can make suitable pdf files for printing is to create a pdf and generate an online proof from it.

WE RECOMMEND THAT YOU USE ACROBAT DISTILLER TO CREATE YOUR PDF FILES
The best way to make a pdf is to create a postscript (.ps or .eps) file and use Adobe's Acrobat Distiller to convert it to pdf format.
If you don't have access to distiller you can download free tools to do the job or you can use one of the various free internet services to create a pdf online. Adobe offer an online pdf distilling service on their website.  

Export Settings
You need to use the correct settings when creating a PDF. Below are some common examples of settings often required by PDF creation software.
Version compatibility : Acrobat 4, version 1.3
ASCII format : No
Resolution : 2400dpi - 3000dpi (target device resolution NOT picture resolution)
Colour Bitmaps : Resample to 450dpi, JPEG compression at maximum quality
Greyscale Bitmaps : Resample to 450dpi, JPEG compression at maximum quality
Mono Bitmaps : Resample to 1200dpi using CCIT 4 compression
Text and Lineart : Compress
Fonts : Embed all fonts or convert to paths/curves. Turn off subsetting.
Colour : Either convert to CMYK or leave colour unchanged.
Overprint/Trapping : Preserve document overprint/trapping.


REMEMBER : To add required bleeds and gutters. Convert everything to CMYK that should be CMYK and everything to greyscale that should be greyscale. Colour bitmaps should be CMYK only and greyscale bitmaps should be greyscale only. There should be no RGB objects in your final pdf.