If you regularly work with Photoshop, whether as a professional or a semi-pro, you will probably have to print a large format image at some point. But unless you know what you are doing, you risk having the image come out blurry or the colors being ‘off’.
One of the main concerns with large-format digital printing is ensuring quality when the image is enlarged. This is often easier said than done. If most of your work involves printing to a standard size, you should be aware that printing enlarged images is a somewhat different process.
Any errors in printing will be magnified when you enlarge the image. After all, a poster or billboard is considerably larger than a brochure or a magazine page. For this reason, you need to keep certain fundamentals in mind when preparing images for large format printing.
Steps for Preparing Files for Large Format Printing
The approach for preparing files in Photoshop may vary depending on the requirements and preferences of the individual. That being said, you will generally get better results by following these steps:
Optimizing the Image for Large Format
The first step is to optimize the image so that it appears as intended from a particular distance. This involves determining how far the viewer will be and setting the appropriate image resolution for that distance.
Images intended for posters or magazines are commonly printed at a resolution of 300 dots per inch (dpi). This refers to the number of ink or toner dots applied to every inch of the image.
For banners or point-of-sales displays, a 75 to 100 dpi resolution should be sufficient since the viewer’s eye will ‘fill in’ the missing image information between the dots. Setting the resolution to 300 dpi is unnecessary and will only inflate the file size and increase the length of time it takes to print the image.
Calibrating the Computer Screen
Printing errors typically result from discrepancies between how the image looks on screen and when it comes out of the printer. Specifically, colors may be off, or sections of the image may be cropped out.
Most of these issues can be avoided by proper screen calibration. This involves setting your monitor to the industry standards for color, contrast, brightness, and gamma. You will generally get the best results with these values:
- Black: 0.4
- White brightness level: 95
- Gamma: 2.2
- White color temperature: 6500K
Monitors should be recalibrated to these settings every 30 days. It is also advisable to convert files to the CMYK color space to ensure a closer match between the screen image and the final print.
Proofing Using Photoshop’s Tools
Aside from proofing in CMYK, it is also a good idea to check your image using Photoshop’s soft-proofing feature. This essentially displays the image as it will look when it is printed onto the final material without altering the pixel information making for some of the best print proofing available.
Soft-proofing compensates for the increased contrast and wider color range displayed by monitors after they are calibrated. If you don’t check your image with this feature beforehand, the final print will likely look considerably different from the image displayed on your screen.
Converting Fonts to Vector Art
If your page or image includes text elements, make sure to convert them to vector art before exporting the file and turning it over to the printer. If you neglect this crucial step, your text may not appear correctly because the print shop may not have the same font files you used. Your text would then be converted to the default font, which could ruin your intended design.
Of course, you could send the necessary fonts along with the image files so that the printer could install them on their computer. But this complicates the process unnecessarily and increases the chances of something going wrong. Converting the text to vector art will prevent potential issues and simplify the process.
Saving the File for Large Format Use
Finally, save the file in a format that the printer can use. Most shops will request EPS or TIFF files, although it might be a good idea to talk to the printer beforehand to find out the specific file format they require.
Preparing images for your large format printing company isn’t that complicated, especially if you are familiar with Photoshop. But you do have to keep the steps outlined above in mind. Over time, the process will become second nature, so you will eventually be able to produce high-quality digital images without too much thought.