As digital cameras have become ubiquitous, and cheap (or free) photo websites plentiful, more people than ever are using images in presentations. Images are not appropriate for every kind of talk, but even when images are appropriate (such as keynote/ballroom style presentations), people are still making the same common mistakes. So here are some things to keep in mind if you use images in your next talk. (Get a larger version of the "slides" image here.)
Case study: a single slide
Let's imagine you are preparing a presentation for a large audience on current issues in Japanese education. One issue facing schools and universities in Japan today is the decreasing number of potential students due to fewer children being born. So our sample slide touches on the low fertility rate in Japan in this context. You could either use a full-bleed image like the one on the left below or a smaller image of a photograph of a school yard in Japan as seen on the slide on the right below. If you chose the slide on the right you could also have a simple line chart fade in as you talk about the declining rate as a long-term trend.
The common mistakes
For our sample here we'll use the photo on the left above as a starting point. How many different ways could we use the same image (at different resolutions) inappropriately or use a different image in a way that is less effective than the one on the left? Here are eleven common mistakes:
(1) Image is too small
You do not have to go full bleed with an image, but this particular image does not work at a such a small size (The slide is 800x600, this image is 183x152.)
(2) Image is placed randomly on slide
The image may be large enough now to be seen easily, but it's put willy-nilly on the slide. Usually this results in the text getting lost in the background (though in this case the text is still legible). Looks accidental.
(3) Image is almost full-screen but not quite
Again, nothing should look accidental. This looks like they were going for the full-bleed background image effect but just missed. Now the software background template can be seen just enough to become a bit of noise
(4) Image is of poor quality (pixelated)
This is all too common. This happens when you take a low-rez jpeg (from a website, for example) and stretch it out. Oh, the humanity!
(5) Image is of poor quality & contains watermark
Even worse is to take a free comp from a photo website and stretch it out. This introduces distracting visual noise (and says you are either cheap, lazy, or both). If you cannot afford images (or do not have a camera, etc.), then it's better to use none at all.
(6) Image is stretched horizontally & distorted
This is all too common. This occurs when people stretch out an image to make it "fit."
(7) Image is stretched vertically & distorted
This becomes a distraction and looks odd. Are young Japanese students really 8-feet tall these days?
(8) Presenter tiles image
Just because the software lets you tile an image, does not mean you should use this feature. Now the background image has too much salience (even if it did not have watermarks).
(9) Clip art is chosen
Avoid off-the-shelf clip art (though your own sketches & drawings can be a refreshing change if used consistently throughout the visuals).
(10) Image is lame & has nothing to do with content
Not sure what two guys shaking hands in front of a globe has to do with the fertility rate in Japan. Yet even if we were talking about "international partnership" the image is still a cliché.
(11) Background image has too much salience (text hard to see)
Sometimes the image is actually a pretty good one but it just needs a bit of editing so that the text will pop out more. The slide on the left below is not horrible but the balance is off and the text does not pop out as much as it could. For the slide on the right below, the image is cropped for better balance, giving more space for the text to breath (and a transparent box is added to help the text pop out a bit more, though there are other ways to do this).
Text & images
Text within images is but one way to use text/data and images harmoniously. As always, much depends on the topic and the context. Images can be very powerful and effective if used with careful intention. The question is not do you have too many? or too few? but rather what's your intention? You can give a good presentation without any images at all, but if you do use images in slides, try to keep these eleven tips in mind.
There are clearly more than eleven ways to use images inappropriately, what are some of the ones that you have observed over the years? Would love to hear your stories.
Update: Here are a few different (though similar) ways to use images in a slide featuring a quote on my personal blog.