Good visual support material is essential when giving a research presentation. No one would think of giving a scientific lecture without a set of Vu-graphs to support the words with pictures. Unfortunately, badly designed visual aids do nothing to enhance understanding and can even confuse and distract the audience. Here are some of the most important elements of effective visuals.
Less is more
Inexperienced presenters tend to put too much material on a slide. But the human mind can only take in so much information at one time. A slide with twenty bullet items will be overwhelming to a viewer: it is too complex; it cannot be comprehended as a unit. As written reference material such a slide may have value, but as a visual aid during a lecture it is useless. Break up printed slides into bite sized pieces: five bullets are fine; eight are usually too many. Fifteen? Forget it.
Crowded slides are also hard to read. A bizarre but all too common scene is watching a presenter display an “eye chart” of a slide, realize that no one can read it, apologize and proceed to develop his argument around it. When creating visuals, follow the two meter rule. If you can’t read them this far from the computer screen, your audience won’t be able to read them from their seats.
There is a place for complicated slides. A long reaction sequence may be effectively presented in one slide—if the structures and print are legible and if the sequence follows a logical order. Drawings are easier to take in than printed words (if they are well drawn!), and the effect here is of building a structure piece by piece. Each step of the reaction sequence stands on its own as an understandable unit but is also part of the overall story told by the slide.
Tell Them and Show Them
The headings of a slide are important to reinforce the speaker’s words. Each heading should summarize what’s shown on the slide. Instead of writing a vague, “NMR Data” write “NMR Data Indicates Vicinal Hydrogens.”
Modern word processing programs give the presenter an almost unlimited choice of visual devices: color fonts, animated fonts, fade in/ fade out of slides, catchy backgrounds, photo insertion, video insertion. Well used, these techniques can increase a presentation’s effectiveness. Badly used, they can detract from it. A slide with a background displaying waves crashing on a beach may be striking, but printed words may be unreadable when they overlap the white of the foaming crests. And the background may be so dramatic that it’s distracting. I love videos and photos that illustrate a speaker’s words. I don’t care for vibrating, florescent captions that serve no purpose. When tempted to use a special effect ask yourself, does this add to the understanding of the material? If in doubt, take it out.