The Ghent Workgroup, or GWG, has put together preflight specifications for the sign and display market and is now running a public beta testing program. This is aimed both at software vendors that want to prepare for standardized quality control and at end-users who can use the preflight profiles to improve their quality control.
David van Driessche, executive director of the GWG and chief technology officer at Four Pees, points out that the sign and display sector covers a very wide area from banners to car wraps, noting: “Each of these products has their own technical requirements and capturing all of them in one specification was no easy task. After some research, it became clear we would have to introduce two key variables – viewing distance and scaling factor – to derive one specification.”
One option would have been to create different specifications for each distinct area in the sign and display market but van Driessche argues that would have introduced extra complexity and been difficult to maintain. He adds: “instead we incorporated the concepts of viewing distance and scaling factor and end up with one set of rules for the whole market segment”
One of the issues that the GWG has addressed is viewing distance, which can vary considerably in the wide format sector, and affects the desired print resolution. This in turn has a direct impact on productivity as lower resolution images can be printed faster. Another widely used concept is scaling factor where many designers create their PDF file at half, 1/10th or even 1/48th of the final printed size to overcome limitations in some editing applications ability to handle large files.
Many wide format printers support a very wide colour gamut so this new specification opens up which color spaces can be used in a PDF file. This is the first time that a GWG specification allows the use of colour spaces such as calibrated RGB or L*a*b* for all elements within a PDF document.
You can download the technical specification document together with preflight profiles from callas software and Enfocus from the new Sign & Display area on the GWG website. There’s also a link to a webinar explaining how it works. It’s worth keeping an eye on this site as the GWG says that it will add more information later. It’s an incredibly useful resource, especially given that the GWG makes its work available for free.