The key to a successful design project is upfront planning. For the best results, you’ll need to know from the beginning whether the final product will be digital-only or will be printed. When planning to create a physical print of a digital image, there are a few technical items you must get right in order for the project to be successful.
The most important is colour, which is handled differently for print and digital images. You’ll also need to choose proper resolution and file formats. Here we provide an introduction on how to prepare your work for print, along with further resources to delve into the technical aspects of colour management.
Resolution is key
When an image will be printed physically, you need to consider image resolution (measured in dots per inch (DPI) or pixels per inch (PPI)). A resolution of 72 DPI is commonly used when publishing for the web, but for creating a print document the industry standard is 300 DPI.
A 300-DPI resolution ensures that images stay crisp and sharp, though for a softer image you might want to use 225 DPI or a little lower. It is difficult to change a lower-DPI file to a higher resolution after the fact without ending up with a muddled, blurry image, so make sure to start working in your desired DPI from the beginning.
Understanding the RBG to CMYK colour conversion process
RGB represents the colour combinations of red, green, and blue used by cameras, scanners, and digital displays. Computer monitors display colours by mixing varying intensities of these three spectrums of light, resulting in millions of potential colours. This is exponentially more colours than are possible using the physical printing process, which has only thousands of colours available.
A full colour, also known as a 4-colour printing process, uses mixtures of the pigments cyan, magenta, yellow, and black (CMYK). When creating a physical print of your digital graphic, you’ll need to convert from the RGB to the CMYK colour scheme.
Plan to put all final touches on images and make any colour corrections before actually doing the conversion. Conversion to CMYK will be the final step after you are happy with all the changes in RBG format. You should always save a final copy of your project in RGB format before making the conversion, so that you can return to the original if you need to make changes at a later date.
High-end graphics programs
High-end graphics programs will have a proof setup function that lets you see your on-screen design as if you were working in CMYK, so that you get an accurate view of how the final print will turn out.
For Photoshop, choose View > Proof Colours. Photoshop also offers a “gamut warning tool” to warn you of colours that may be difficult to convert.
If working with logos in Adobe Illustrator, you can start out working in CMYK mode, eliminating the need for conversion. If working with InDesign, you can combine RGB art elements and CMYK logos in the same document. The ‘Proof Colours’ feature gives an accurate view of what the RGB images will look like after the conversion.
Real World Colour Management provides a great primer on colour theory and management, and how to fine tune-printing profiles to get the exact results you want. Working with the colour black can be especially tricky, and there are many potential variations. This guide to working with black describes the different settings to use and when they are appropriate.
The industry standard for delivering a CMYK file is a PDF. To export a high quality PDF for printing, Adobe has a ‘press quality’ option in InDesign. For Illustrator, choose ‘Adobe PDF’. If using another graphics program, choose the PDF/X-4 option to guarantee that all the necessary fonts for printing are included.
The encapsulated PostScript (EPS) file format is sometimes favoured for submitting logos. EPS is a vector format, allowing the graphic to be resized without losing any image quality. The Adobe Illustrator (AI) format is also vector based and is sometimes used to submit logos.
By understanding your options and deciding up front whether a project will be print based or all digital, you can avoid common problems and be set up for a successful project completion.