We’re entering talk season, with a bunch of conferences coming up from May through August. I recently ran across an old article/talk from 1988 (updated in 2001) by Jim Blinn, Things I Hope Not to See or Hear at SIGGRAPH – find it starting on page 17 here. Short version: read it. Some of it’s dated (“don’t spend a lot of time fiddling with the focus”), much is not. You may disagree with some of the ideas there, but it’s worth 10 minutes of your time to check your assumptions. Plus, it’s funny.

Bits I particularly like (honestly, I could quote about a third of it – these are just teasers), slightly out of order, with my own views:

“Many of you are involved in the microcircuit revolution and tend to think this also applies to the text on your slides. It doesn’t. My personal rule is to put no more than six lines of text on any one slide.” – I see this guideline broken a fair bit nowadays, 17 lines on a slide, “hey, we have high-res displays.” You could probably project a whole page of text on the screen – would you? Why not? So, what’s your limit?

“But, you may ask, what if I have more than six lines? Well…just use more than one slide. See? Simple.” Honestly, slides are free. Admittedly there’s a tradeoff with having to read a new slide when it comes up, versus having everything laid out in one slide. But, there’s an excellent reason to avoid busy slides:

“The audience is not going to want to read a lot of text while simultaneously trying to pay attention to what you are saying. Text on slides should just consist of section headings.” If you’re reading your talk off the slide, that’s too much text. I think of the slide’s text parts as bits that fall in between the speaking, giving some structure and helping when attention wavers. There’s also a tendency to make the slideset a self-contained presentation. “You missed my talk? Well, my slideset explains it.” Please don’t. Or do, if you can’t blog or write an article about it, but put the detailed explanation in the notes section for each slide, not in the slide itself. I’ve even seen the speaker’s words in the notes section in one slideset, something I suspect we’ll see more of with AI assistance (cue amusing mistranscriptions – two weeks ago I saw for a speaker’s “there’s a handy link here” a closed caption of “there’s an ambulance here”).

“Don’t put more than one equation on a slide unless it is fantastically necessary.” My rule is to almost never put an equation in a talk, versus the ideas behind the equation, unless the talk is truly about that equation and it’s worth understanding the terms as presented. Equations are like super-dense encodings, a page of text compressed into a line. I don’t expect the speaker to pause and the audience to read and understand three hundred words projected on the screen, so I shouldn’t expect them to read a new equation and comprehend it during a presentation. If you do focus on an equation, his advice:

“Recast your equations into simpler chunks and give each chunk its own name. Make one master slide with the basic equation in terms of these names. Then make a separate slide to define each chunk.” I try something like that here.

“Look up at the audience; it looks a lot better for the TV cameras.” I am guilty of staring at the slide on my laptop’s screen, or worse yet, turning away from the audience and talking to the projected slide.

“Probably the most important parts of your talk are the first and last sentences. Have these all figured out before you go up to the podium.” And, with that in mind, Jim’s ending:

“Look up. Bright slides, big letters.
Uh, I guess that’s all I have to say.
Thank you.”