Setting up correct colour separation for Press Printing is one of the most critical things to get right when setting up art for print. If your colour separation is incorrect, parts of your art could go missing in the final print result. Printing presses use ‘plates’ and there is an individual plate for each colour ink that is to be used for the particular print job.

A common problem with the amateur designer trying ‘do it yourself’ is that they use programs like Microsoft Word which are actually incapable of setting up colour separations for press printing, rather they only use RGB format which is primarily used for screen or television viewing.

For 1, 2 and 3 colour press runs, your file needs to be saved in “spot colours” such as “Pantone” colours. In most programs that are capable of setting up jobs for press, you will find an option in your colour palette to create and save a colour as a “spot colour”.

In the case of a single colour press run, one option would be to save it all in black, if unsure of how your colour might separate as a pdf.

For a full colour or 4 colour print job you must ensure that your file and all related links are saved as CMYK (Cyan, Magenta, Yellow and Black).

Lisa

Lisa is a graphical and pre-press designer with more than 15 years experience. She runs her own agency Twilight Emerald from Ballarat, Victoria Australia.

Below are some tips for scanning or saving images for press printing in different colour formats:

Full Colour/4 Colour Images
All full colour digital photos and raster images need to be saved in CMYK format, preferably as “eps”. Resolution for full colour images must be a minimum of 262ppi (pixels per inch) or up to 300dpi when saved at 100% actual size.

Greyscale Images
Greyscale images (or black and white photos) need to be saved in “tiff” format at a minimum of 300ppi (pixels per inch), when at 100% actual size.

Bitmap/Line Art Images
Line art, text or bitmap images need to be saved as “tiff” format, with a minimum of 1200ppi (pixels per inch) when at 100% actual size.

All scans and digital photos must be created at the above mentioned resolutions originally, as re-sampling to a higher resolution at a later stage will not increase the quality. The only way the resolution may be increased at a later stage, in some cases, is if the image is originally much larger than the actual size required. In reduction the pixels per inch may be increased in proportion.

Note: “ppi” (pixels per inch) and “dpi” (dots per inch) are similar terms. Different programs may refer to either one.

To print pictures with enough quality the electronic file needs enough information to do so. Web/internet images have a resolution of 72dpi for screen viewing only, and are not suitable for press printing. They appear pixelated and unclear in print.

Lisa

Lisa is a graphical and pre-press designer with more than 15 years experience. She runs her own agency Twilight Emerald from Ballarat, Victoria Australia.