• About Portable Document Format (PDF)
   
• Creating a PDF
   
• About Vector and Raster Images (PSD VS EPS VS TIFF VS JPEG)
  
  • EPS Format
  
  • PSD Format
  
  • JPEG Format
  
  • TIFF Format
   
• Proofing Process

 
  ABOUT PORTABLE DOCUMENT FORMAT (PDF)

• It’s a flexible and convenient file to work with.

• It’s device independent i.e. it can be viewed on a computer, mobile device, etc. without any defects.

• Small in size, but completely self-contained, meaning you can convert your file to PDF without compromising quality.

• It’s designed for the transfer of documents between different operating systems e.g. Mac Os, Windows, Unix etc.

• Designed to overcome incompatibly problems or inability to read fonts etc.

• PDF file is a platform independent file, and can be viewed and printed on Mac, Dos, Win or Unix systems.

• All graphics, fonts and elements are embedded.

• It allows the sharing of the most complex information between different operating systems.

• PDFs are also suitable for those who wish to have a publication in electronic format while still maintaining the original layout.

• Correctly configured PDF files are reliable and predictable, and therefore create efficient workflow.

• Composite PDF files limit the last minute editing of text, graphics etc.

• PDFs are the preferred way of working for large printing companies worldwide.

 
  CREATING A PDF

• When creating a PDF use ZIP (no loss of information) image compression instead of JPEG (significant loss of information dependent on quality setting). Your file will be larger but the upside is that there will be no loss of quality. Under circumstances where disc space / bandwidth is not an issue turn compression off altogether (this will allow for faster file processing). Ideally JPEG compression should only be used for PDFs that will be used on the web.

• If your PDF export dialogue box has a colour setting window make sure that the colour management is set to leave the colour unchanged. If you choose RGB your file will be useless and if you choose CMYK any spot colours you may have used will convert to process.

• Always embed all fonts. Due to licence restrictions on some fonts, not all fonts can be imbedded, it’s best to convert strange fonts and symbols to curves / path / outlines.

• Make sure your file contains no OPI links or DCS files before exporting them as PDF. These are only meant to be low resolution placeholders for high resolution images. Confirm that the high resolution image has been embedded into the PDF.

 
ABOUT VECTOR & RASTER IMAGES: (PSD VS EPS VS TIFF VS JPEG)
 
  EPS FORMAT

• The Encapsulated PostScript, or EPS file format is the preferred format for importing vector-based images. When saving a Vector image in EPS format no changes are made to the original file quality.

• It is the universal way of saving files from FreeHand and Illustrator and is often the best method for saving raster images from PhotoShop.

• The EPS file format allows the use of clipping paths to mask objects, the saving of Duotones with Pantone Colours or files with spot colours & the option for saving whites as transparent. This enables users to set the background colour later in a page layout application.
 

  PSD FORMAT

• The PhotoShop Document is the smartest and most reliable method for saving files from PhotoShop for import into programmes that support the file format (e.g. InDesign). PSD supports transparent backgrounds and layers.
 

  JPEG FORMAT

• JPEG files are compressed versions of bitmapped images. The quality is lower (in varying degrees depending on the quality setting chosen) than that of EPS or TIFF files and the format should be used with caution when files are saved with printing in mind. A definite no-no is to open a JPEG file and then resave it as a JPEG as the quality of the file deteriorates dramatically with each save. It is more suited to web applications where quality is not as important as speed.
 

  TIFF FORMAT

• The Tagged Image File Format, or TIFF, offers a convenient means of saving graphics that are scanned or generated electronically. It supports only bitmap images and cannot be used for vector images. Grayscale or Bitmap images saved as TIFFs can be altered after being imported into programmes by manipulating certain attributes (for example colouring the image) TIFF supports LZW compression (no data or quality is lost) but this feature should not be used when sending files for platemaking – consider sending PDFs instead.