by Jon Hooper
This column is a series designed to help enhance your PowerPoint presentations. Each edition pinpoints common pitfalls faced when planning, preparing, and presenting PowerPoint shows.
Pitfall: Importing Low-Resolution Internet Images
“Homer, I need photos of ducks for my PowerPoint show.”
“No problem, Marge, I will just grab some images from the Internet.”
Figure 1. Low-resolution images that fill the screen often look “pixelated.”
But there is a problem, Homer! Many Internet sites use small, low-resolution images that allow the website to load faster. When imported into PowerPoint and expanded to a more desirable size, these images become “pixelated.” In other words, the small, square pixels that make up the image become visible to the eye and the image does not look sharp (see Figure 1).
To purge the pitfall: The best “resolution” (har, har) to this problem is to import medium- to high-resolution images. If you do not know the resolution of an image, import it into your show then project the slide at the size your audience will see it. If it looks sharp, you are in business. If the image you need is only available in low resolution, keep its size small on your PowerPoint slide.
Figure 2. Keeping an imported low-resolution image small and adding text around the image can give a more acceptable overall appearance.
Consider adding sharp-looking text above, below, or next to the low-resolution image to give the slide a more acceptable overall appearance (see Figure 2). If adding text is inappropriate, consider importing more than one image onto the slide so you don’t end up with too much “dead space.” For example, Marge might add shots of several different ducks to each slide.
Pitfall: Not Compressing Higher-Resolution Images
“Homer, thanks for only loading higher-resolution images into my PowerPoint show. Everything looks sharp, but now my show takes forever to load—and sometimes it freezes!”
“Marge, don’t sweat it. We’ll just delete the last half of the show to solve these problems.”
While higher-resolution images give your show a sharper look, they also make your show’s file size larger. This increases the time it takes to load the show (it is really nerve-wracking wondering if your show is going to load) and can cause your computer to freeze.
To purge the pitfall: PowerPoint’s “Compress Pictures” feature is a better solution than Homer’s “delete the last half” idea. This feature discards unnecessary data from each picture without reducing the picture’s quality. Before you initiate such a compression, however, give the show a new name (so you will be able to distinguish your compressed show from the original, uncompressed show). For example, you may want to save your “Tahiti.ppt” show as “TahitiCOMPRESSED.ppt.” If, for some reason, you do not like how the compressed show’s images look, you can go back to the original.
Final Thoughts
PowerPoint shows that contain sharp images capture and hold audience attention better. The guidelines above will help you achieve such shows while keeping file sizes manageable.
Dr. Jon Hooper has over 30 years of experience helping natural and cultural resource professionals enhance the effectiveness of their communication efforts. He is a professor of environmental interpretation at California State University, Chico, and is the owner of Verbal Victories Communication Consulting. He is a Certified Interpretive Trainer (CIT) and was Project WILD’s national Facilitator of the Year in 2006. Contact Jon at jonkhooper@hotmail.com.
Another image pitfall is inappropriately using copyrighted materials found on the web. A good way to find high quality photos for PowerPoint presentations is by searching at http://www.creativecommons.org, which is a site dedicated to helping people share their work. The gateway allows you to seach Flickr.com, a photosharing site, for images that people have entered under the creative commons license intended for people to share.
Another source of professional photos is Pbase.com. These are almost always labeled “all rights reserved,” but a quick email to the artist has been all it took for me several times to get permission for PowerPoint and printed materials.