When you use images in your presentation you can make them have more impact by doing one simple thing: fill the screen with the image. In the printing business this is called full bleed.
You've more than likely come across a book, magazine, or pamphlet that has a full bleed image. The great thing about full bleed images is that, rather than feeling like you are looking at a picture, you almost feel like you are in the image itself. That is because all distractions are removed by printing the image all the way to the edge of the page.
To make a slide have more impact and to avoid distracting elements, scale it up to fit the entire slide (or even larger if you want to focus on a certain element). Do not leave any portion of the background showing. Take a look at the following examples:
In the original, I simply placed the image in the slide as the template suggested. It's fine, really, until you see the second option. Here I filled the entire slide with the image. This changes the viewer's perspective from looking at a picture to actually being in the picture. Also, it actually made more room to place the text - right on top of the image.
Troubleshooting
Now, I will let you know right up front that you will run into two problems with this approach.
First, you may want to use an image that is in portrait orientation rather than landscape (meaning it is taller than it is wide). If you were to fill the slide with an image like this you would have to crop it and most likely lose nearly half of the image.
The solution is simple. Use a plain black background and fill the slide vertically while leaving margins on the side. When the image is projected on the screen, those dark margins will simply disappear because they blend in with the rest of the unused projector screen. Softening the edges of the picture will remove any sharp lines and help the photo to blend in even more.
Second, after you scale the images to fill the slide, they may become distorted or "pixelated". If this happens, the image you are using does not have high enough resolution. Most projectors have a screen resolution of 800x600 pixels. (Newer models have 1024x768 or even higher if it is a widescreen projector.) In fact, 800x600 is the default resolution of new presentations in most software. If your image has a lower resolution and you stretch it to fill the screen, some detail will be lost.
So be sure the images you use have a resolution of at least 800x600 pixels in order to fill the screen and maintain full quality.
In a future post I will explain how to determine the resolution of an image and even how to quickly find a suitable image on Google or Flickr.