Setting Up Design Files for Large Format Printing
Has your large format printer ever told you your images needed to be 300 DPI or they would be pixelated? Here’s what that means and a few other key items to consider when submitting design files to your large format printer.
Designing to Scale
To reduce errors and simplify the printing process, it is best to set your file up at full size. But all graphic design programs have size limits. InDesign’s maximum dimensions are 216 inches (18 feet); Illustrator’s are 227.5 inches (19 feet) and PowerPoint’s are 56 inches (4.5 feet). If your final output size is larger than the maximum dimensions of your design program, you will need to design your file at a percentage of the final print size -either 25%, 50% or 75%. The percentage you use depends on the final size. Your printer will scale the file proportionately larger to meet the final print size. Communicate your scale and print size with your printer to avoid any oversight. Here’s how to make sure that scale does not affect the clarity of your images.
Images
There are two types of images – raster and vector. Raster images are made up of pixels. These are tiny squares that you can see if you zoom in close enough. Pixelation is the term used to describe the blurriness of a raster image when it is viewed at too high a magnification. Some raster file formats include: JPG, GIF and TIFF. Raster images are not ideal for large format print pieces, especially if you are designing at a percentage of the final print piece. Because of the pixels, raster images can blur – depending on the resolution – when scaled up.
Vector images, such as EPS and AI are the preferred image for large format printing. Vector images use mathematical calculations that form lines and shapes from one point to another. Vector images don’t pixelate because the equation recalculates to accommodate zoom. So vector images are unlimited in their scalability.
Resolution
Another criterion your large format printer may specify is your image resolution. Dots per Inch (DPI) are the number of individual dots that can be placed in a line within the span of 1 inch. Pixels per Inch (PPI) is the same measurement but is used in reference to raster images. It is recommended that all images be 300 DPI at the final size of the piece. While 150 DPI can work for some large format pieces, 300 DPI is the recommended image size. This doesn’t mean you can not include images that are lower DPI. Just be sure to let your printer know so they can make recommendations to optimize print quality.
Check back in a few weeks for important information about bleed, trim size and color builds for large format printing.
Creative MediaWorks offers custom web development, graphic design and print solutions to the Life Science industry and their agencies with a focus on quality, deadline and accuracy. We achieve our quality standards through defined workflow processes, direct access to on-staff project talent and proofreading and quality assurance expertise, backed by an uncompromising commitment to the most responsive customer service in the business. For more information, visit our website www.CreativeMediaWorks.com.
