How important is hi-resolution imagery, especially for projects that are going to be shown several feet in width and height?
A. Hi-resolution imagery is important for our industry. Most printers (for traditional print projects) request the resolution to be, at full size, 300dpi. However, for large-scale projects (billboards, trade-shows, large scale packaging displays, banners) this is not necessarily the case. It would almost be impossible to find images that are 300dpi in feet. The truth is that it is not necessary to have 300dpi images at full size for these types of projects. Why you may ask? How is this possible? Well the answer is quite simple, the distance at which you are viewing a hand-held print piece is quite different than viewing a large scale billboard or trade show design. Since you are viewing these from a distance, the slight pixelization that occurs from working with what would normally be considered a lo-resolution image is not evident.
So then, what size imagery is necessary?
Well, they still need to be rather large in file size, but most request a file to be designed using anywhere from 100dpi-150dpi (depending on project/printer specs). This is the case for any image that is created using the pixel based design program, Adobe Photoshop. If you are creating artwork using the vector based program, Adobe Illustrator, then you do not need to concern yourself with any dpi whatsoever. In fact, Illustrator is quite accommodating when it comes to large scale production because it is vector based, the images could be scaled to a very large size without any distortion.
How do I know if my photo is large enough?
This is quite simple to check. All you need to do is open up the photo in Photoshop and go to the menu - Image - Image Size - to bring up a dialogue box that has all of the pictures details, resolution and size in pixels and inches. So for instance, if I have a photo that is 120.8megs @ 300dpi (see diagram below), all you need to do is change the resolution to 100dpi BUT keeping the file size the same.
Billboard imagery works using the same principles, but what they do is give you a proportion to work with. For example a 30' x 10' billboard would need to be created usually at 1/4 size in proportion, to the final size, using the 100 or 150 dpi pixel dimensions. Since they enlarge your file during the printing process, much pixelization occurs but, because of the principles I mentioned before on how you are viewing a billboard image, at a distance, the viewer never sees this. Also important to mention, most billboard companies have been doing digital billboard spaces instead of printed poster bulletins of late. Essentially, digital billboards are prepared with an even lower resolution, 72dpi, because that is the screen resolution for any digital project. Make sure you review the billboard options and specs directly with your billboard rep, as there is not one set billboard size, usually several to choose from. When choosing a billboard space, you must consider the location and price (higher traffic locations usually are more expensive), as well as the time of year it's available (planning several months in advance to reserve a specific location is necessary).
What color mode should I be working in?
You must check with your printer for detailed specs on what mode they would like to receive the files in. But most require files in rgb mode. This is the direct opposite of what you do for normal print production where you are preparing files in cmyk mode. Also, special techniques (varnish and Pantone Spot colors) are not acceptable for large scale projects. Even though these are printed projects, they not printed on traditional offset printing presses, rather large format digital presses. The paper or material comes in a roll, and is usually vinyl or a heavy material appropriate for the project, and this material can't be used in for offset printing, because of the thickness and size.
What is the proofing process for a large scale project? How do I sign off on a proof that will be printed so large for final production?
Usually a digital pdf proof is given for sign-off. Unlike print production projects, where I normally advocate against signing a digital print because you are viewing a rgb file for cmyk printing, since these files are created in rgb, reviewing a digital proof is acceptable. You still should be aware of how your screen is calibrated and may want to ask for their monitor profile settings, but the color quality should be almost exact to what you sent. If you are truly concerned with reviewing a digital proof, then you could certainly request a print proof, they will provide a small print out on the actual material it is going to be produced on. Some companies may charge a small fee for this proof, you should discuss this with the account rep at the onset of the job.
Some additional tips:
- For trade show displays: remember you are working in feet and the displays are usually tall and vertical, so remember that no one is going to bend down to read or see images below their torso. Try and keep any important information above the waist – this will affect your design and layout decisions. Having a blank area at the bottom of your layouts could be quite uninteresting, so consider continuing any background or color to alleviate any negative space that may occur in your design.
- For both trade show and billboard designs: keep in mind that 72points in any font equals 1", so you will be working in very large point size in order to make sure the viewer could read your information. There is nothing worse than designing a billboard or trade show only to find out that the type is too small and not readable.
- For both trade show and billboard designs: InDesign is not the program that you will be using to create your final files, rather Illustrator and/or Photoshop. Again, this is the opposite of regular print brochure projects. If you are working on multiple panels, you will need to create separate files in Photoshop or additional artboards in Illustrator.
Below is a recent example of a trade show display that I designed for a copier distributor company. The middle panel is slightly large in size and the white area in that panel represents a projection area (a video stand goes in front of the middle panel and displays the company powerpoint presentations).
I kept in mind the same principles as outlined in this blog, making sure that no important information is near the bottom of the design. Also, because we knew this project was an extension of their initial print collateral materials that were being designed before the trade show creation, I requested the background photos to be shot at the largest file size possible. When working on any branding or ad campaign from the beginning, make sure you talk about the client's future objectives for the designs you are creating. There is nothing more time consuming that re-creating or shooting image files for large scale print projects because you did not have them from the onset of the campaign.
Remember to plan ahead and check all the final specifications with the company you are working with. Whether it's your first or second or 20th time creating files that are large scale projects, it is necessary to consider these principles in order to make your final projects both technically sound and graphically interesting. I hope you find some of my tips and tricks useful to your process.