Using images in your presentations
Today’s Guest blog is brought to you by Simon Raybould of Aware Plus.
Pretty much everyone who teaches presentation skills – whether you use PowerPoint for your slides or something else – will tell you the same thing… images trump bullet points when it comes to impact and ‘memorableness’ for your images. The question, of course, is how to use them correctly.
I know it’s doing things backwards, but let’s look first at what sort of images you want, and then at how to find those images.
Powerpoint (and other packages) can make a much better fist of scaling images down than up. This means that if an image isn’t big enough to fill your screen you’ve got two options, both of which are ugly.
Firstly, you can stretch the image, with the horrible effect of pixillation or, secondly, you can have your image tucked into a corner of the screen which makes it pretty obvious to everyone that you just added it without much thought or care. Neither option makes you look good.
The solution, of course, is to make sure your pictures are at least as big as your slide to start with and if necessary scale them down.
If you’re getting your images from a commercial site, just tell the site what size image you’d like to download after you’ve found the perfect image. If you’re using Google image search, make sure you’ve gone to the advanced settings and picked the ‘large’ image size. The screengrab below shows you what you get if you search google images for ‘fear’ without the size filter. Neither of the first two results will look good as they are when projected as part of your presentation.
By only searching for ‘large’ images, you can narrow down your search to those which are more useful to you: the second screen grab shows you the first to images you get when you do this – both will work fine (from a technical point of view) in your presentation).
Remember, all we’re talking about here is the technical issue – I’m not saying you should use these images – you need to consider artistic and legal issues before you do that!
So, you’ve found an image that’s big enough to use. What’s next? Look at the ‘contrast ratio’
What the heck is a ‘contrast ratio’? Crudely put, the contrast ratio is the difference between the brightest part of the image and the darkest. At one extreme that will be black and white but in most pictures it’s far less than this. You want to have an image with a high contrast ration because, sadly, most projectors ‘flatten’ the ratio out, giving a kind of leached out effect to the images.
If you start with this kind of ‘flattened’ image, you’ll end up with something very flattened. Have a look at these two snapshots I took on my trusty iPhone at a resent presentation I went to. The first shows how the image should look, displayed on a very large plasma screen at the side of the room and the second shows how it actually looked when it was projected to an (even larger) screen at the front of the room. A pretty striking difference, I think you’ll agree. (I’ve used the wallpaper rather than the slides the presenter was using to protect anonymity of the presenter.
Imagine trying to watch the slides when they’re that hard to see. Yes, you can probably do it but every bit of your brain-power given over to figuring out what the slide shows takes away from the amount of brain you can dedicate to understanding those same contents.
Okay, that’s it for now. I’ll talk about the legality issues next time.
Simon Raybauld is Director of Aware Plus, and an expert in communications training, including the advanced versions of the MBTI psychometric tool Aware run the famous Curved Vision brand of presentation skills training courses. He’s also a professional lighting designer, specialising in work for dance companies. So what if the pay’s rubbish, it’s a lot of fun!
2 thoughts on “Using images in your presentations”
A couple of excellent points that I’ll be giving a lot more consideration to in my future presentations – and I’d certainly never thought about contrast ratio. But now you mention it… I’m going to notice it!
Thanks for your comment, and yes it is something to consider. Like lots of things, once it is brought to your attention, you will remember.
What are your favourite tips about using images in presentations?