Preparing Files for Banner Printing

When it comes to file preparation of large-format banner printing, there’s a different mode of thinking. The traditional rules of file dimension and resolution used in standard offset printing don’t necessarily apply. Where traditional print methods have you working in the 300-dpi (dots per inch) range, large format basically reverses that thinking altogether. This is where a number of traditional print designers and desktop publishers find themselves in unfamiliar territory. There’s a common misconception that bigger files need more resolution than normal print jobs—this is simply not true. All this does is give you a really huge file size.

Preparing files for Large Format Printing does not usually require the higher 300 dpi image files commonly associated with other printing methods. "Large" implies just that. 300 dpi images at large sizes can produce extremely large files - in the gigabytes range. This is usually not necessary and places extra burdens on all raster image processing systems (RIPs). You will find a wide range of opinions when researching this subject. When setting up images with the document size set at full size (the size of the printed product) it is only necessary to set the pixel size at 100 pixels/inch for most types of banners.

Photoshop for Large Format - A Unique Way of Thinking

So why does the preparation of files for large-format output seem to have traditional print designers scratching their heads in perplexity? Let’s consider how viewing distance factors into how we set up a Photoshop file for large-format output.

Let’s say that we have a client who wants a 4x12 feet full-color banner with photos and text. The first thing to consider is: Where is the final image going to be located and how far is it going to be viewed from? Well if it’s going to be viewed from less than 3 feet (like a wall mural), then we’re going to need some detail in there — around 100-ppi (pixels-per-inch) Resolution. So a Photoshop file at 48 x 144 inches and 100-ppi will create a very large file. That’s a lot of data because there are so many dots in a single square inch.

Now if the image is going to be viewed from a considerable distance — say 10’ or more — we can decrease the resolution to around 100 dpi. Now we have a 200 MB file. On some occasions, you can go even lower than that (consult with Printastic first). This is where some designers start to get nervous, but they don’t need to worry. Just remember that the dot size is relative to the viewing distance. The closer your viewer will be to the image surface, the smaller the dots need to be; the farther away he is, the larger the dots. Relative to your eye, the dot is the same size.

You can also keep in mind that if you’re using Photoshop to build your large-format file, Photoshop will only handle a maximum pixel dimension of 300,000×300,000. However since Photoshop CS, and later versions, there is a specific large-document file format designated PSB, which will support your large files while maintaining layers, styles, etc.

What about Adobe Illustrator?

We know that Photoshop is a pixel-based application, which means that it’s resolution-dependent (you may have heard that term before).

Pixel based files - JPEG, TIFF, GIF, PNG

Vector based files - PDF, EPS, AI, SVG

On the other hand, Illustrator is a vector-based application, which means that it’s resolution-independent. Vectors are geometric shapes based on mathematical equations, which means that they can be scaled to virtually any size without even the slightest loss of quality. So if you can get away with designing for large format with all-vector art, you’ll get very high-quality art and a very manageable file size.

Here’s the caveat: This only applies to vector art. You can import pixel based art into a working Illustrator file but this would be a resolution-dependent element that will print using the resolution settings from the original file. Also, embedding pixel based art in an Illustrator file will result in a huge file size, which will take much more time to process. So you’ll want to use Illustrator for sharp, clean graphics and text and Photoshop for photos and continuous tone images.

How To Set Up Your Graphic Files

At Printastic, we print using state of the art Mimaki 8 color Eco-Solvent inkjet print system to produce high quality banners with vivid details and brilliant colors. While you may think that designing files for print in the CMYK colorspace is preferable, we would actually prefer RGB files - making it easier for you and still generating perfect prints.

A few reasons why designing in RGB is easier for you include:

More applications natively support RGB than any other colorspace.
The RGB color gamut is larger than CMYK
RGB File Sizes are about 25% smaller than CMYK. Working with larger CMYK files can cause your PC to slow down, negatively effecting productivity.
Many filters and functions are only available to use in an RGB color mode in PhotoShop® and similar programs.
Working in RGB means that your images are web-ready with no color conversion (as opposed to designing for print in CMYK and converting the color to RGB for web-use).

Since most digital photos and images are RGB, saving as CMYK files will result in a major clipping of the color gamut in some cases. If you look at the image to the right, you can see that converting an image will clip vibrant blue and reds of your web images, making them looking dull unless you experiment with saturation settings within your image creation and photo editing applications.

While it is true that most old fashioned offset-printing presses still require CMYK data to function, our cutting edge inkjet system handles all color conversion and management inside its embedded RIP (raster image processor), making dated printing conventions a thing of the past. In addition, since your monitor (and all monitors) display in RGB, your printed output will closely match what you see on your screen without the need for costly and time consuming printer/monitor color calibration procedures.

Printing Extra Large Images

Working from Mac and Windows Adobe Photoshop applications, we can utilize your files to produce many of our products. These guidelines are very basic and will not guarantee your images will reproduce correctly but may aid in a more trouble free experience. Once we receive your files, they are previewed to make sure they are acceptable for the intended purpose. A Printastic representative will contact you if we determine your images are not of acceptable quality.

Set Document size full size of finished banner or sign. In this example 72 inches width and 36 inches high. Resolution will print crisp if set at 100 pixels/inch - (assuming your original artwork is high quality). Apps other than Photoshop use similar settings.

Pro Tip:
Setup your canvas or page size to the full size of the desired banner or sign in inches. Do not include bleed or crop marks. If you would like to order a 3×8 vinyl banner then create your page at 36 inches x 96 inches. Resolution should be set to 100dpi. Color mode: RGB

General Guides for all file types

While the most Preferred format for designing large vinyl banners is PSD with all layers flattened to a single layer at 150 dpi or more at the final size, there are other file types that are also used. Here are some guidelines for a variety of types.

photoshop

Make your PSD file set to 100dpi at full sign size in inches. As a general rule PSD files less than 1mb in size can not be printed. Flatten PSD to a single background layer. Do not compress or optimize your PSD, save at 100% quality.

Illustrator

Convert all text to outlines. Expand all Fills and Stokes. Save as PDF file.

PDF files

Convert all text to outlines. Expand all fills and strokes.

EPS files

Convert all text to outlines. Expand all fills and strokes.

JPEG files

Make sure your JPEG is set to 100dpi at full sign size in inches. As a general rule JPEG files less than 1mb in size can not be printed. Do not compress or optimize your JPEG, save at 100% quality.

TIFF files

Make sure your TIFF is set to 100dpi at full sign size in inches. As a general rule TIFF files less than 1mb in size can not be printed. Do not compress or optimize your TIFF, save at 100% quality.

Corel Products

Native Corel files can not be processed or printed. You must save your Corel file as PDF or EPS or high resolution (150dpi or greater) TIFF or JPEG

Microsoft Word

Try to avoid using Word to setup the banner. They usually are troublesome and can not be printed. If Word file is all what you have, add a border proportional to your sign size and make your design inside that border only. When uploading your Word file, include all Fonts used in the files in upload.

Publisher

Native Publisher files can not be processed or printed. You must save your Publisher file as PDF or high resolution (150dpi or greater) TIFF or JPEG.

Powerpoint

Native Powerpoint files can not be processed or printed. You must save your Powerpoint file as PDF or high resolution (150dpi or greater) TIFF or JPEG.