Four blog posts: Figures for talks vs. papers, simple tips, images in talks, laser pointers
From these four blog posts: 1, 2, 3, 4
Figures for talks and figures for papers
We've been working on writing up Olivia's paper, and I've also been giving some talks about the work, which has given me a chance to compare those two modes of communication. There are of course many differences, but one of the most striking is that the figures you use for papers seldom work right for a talk. Paper figures tend to be WAY too information dense for a talk. I noticed this recently when I gave a talk on this material and I lazily just incorporated one of our nicely constructed paper figures, only to realize when I was up there talking about it that it would probably take me a good 5 minutes to explain everything in that one picture. Note that this is not just about conveying too much data, but in this case just a diagram to illustrate the comparison between two hypotheses. There is a fundamental conflict: giving a talk, you really can only present one concept at a time and need to make sure people are coming along for the ride. In a paper, you can (and often must for space reasons) present multiple conceptual layers on top of each other. Hence the high cognitive density of those figures.
Anyway, I reconfigured the talk with some rather different figures, and it went much better (or at least I thought so). Maybe something to keep in mind when preparing a talk.
Simple tips to improve your presentations
Lots of stuff out there on how to give a good talk, but if I were to pick my top three tips that would really improve most academic presentations, I would pick these (courtesy of Uri Alon):
Your presentation should be centered around you, not your slides. The slides are your props, but you are delivering the material.
Make sure every slide has a title that is a complete sentence. Sentence, verb, object. This was transformative for me. It ensures that every slide has a point.
Remove all other text from the slide (other than axes, etc.). Text distracts. The audience should not be reading text, they should be listening to you.
Images in presentations
Since Gautham is on the subject of presentation pet peeves, I thought I'd bring up one of my own (along with some solutions).
We do a lot of imaging in the lab, and one of the best things about it is that it can produce compelling images that are fun to show off at a talk. Nothing like a few oohs and aahs to bring the audience back from the dead...
But one thing that always bugs me in talks is the dreaded "Well, you can't really see it so well here, but trust me, it looks really good on my screen..." (and yes, it's happened to me many times). This is often accompanied by a valiant but typically doomed attempt to show the image on the laptop to someone in the audience to try and corroborate the claim. What are the common reasons that images look bad on the screen? Here are a couple along with some suggestions.
Image features are too small to see. We have a lot of RNA FISH images that we like to show off in talks. Which of course brings up a problem: the RNA spots are really small, and often we want to show off multiple cells. Or, even worse, comparisons between fields of cells. The temptation is to put those fields next to each other and shrink down the image. The problem then is that the images become so compressed that nobody can see the spots anyway. So then what's the point? If you have an image scale issue, one solution is to break the problem down. Show the outermost scale to get people oriented (along with markers that are actually visible at that scale), then show a little box around the area, and then zoom in.
Merges. Gautham covered this nicely. Merges usually just look really bad. Try not to use them. There are a few situations in which they can be useful, but they are rare.
Contrast is to low. This is actually an issue that's even more pronounced in print. The problem is that stuff that's obvious when you're sitting right next to your screen is hard to see on the projector. I think this is because when you are close up and have time to pay attention, it's easier to focus on what are actually rather subtle features in the image.
Settings on Apple Laptops
Here's another seemingly arcane but often crucial little trick. Despite my best efforts to adhere to the above rules, a few years ago I noticed that after I updated my laptop's OS, I found myself repeatedly saying "Well, somehow this isn't looking so good on the screen, but what you should see is..." Very embarrassing! And I just could not for the life of me figure out why my images were looking so crappy on the screen. Then, after some digging, I figured it out. Turns out that when you plug in a external projector (or monitor or whatever) to your Mac, it chooses a color profile for that device. This governs how the colors look on the screen. The issue is that a couple years back, Apple updated things so that the default color profile when you connect has terrible contrast for many images. The solution is to open "Displays" in System Preferences, then go over to the output screen, click on the "Color" tab, then uncheck the box marked "Show profiles for this display only", and then select "sRGB IEC61966-2.1". Anyway, after I did that, all those weird problems went away. But only after dealing with the first 3 items...
A case against laser pointers for scientific presentation
By Gautham Nair
Laser pointers are the most common, and they invariably make for a poorer presentation than without it. Here are the three fundamental problems with the use of laser pointers in talks.
Laser pointers do not point at things, they point on things. In fact, the term "laser pointer" is a misnomer. It is just a laser point. It does not produce a pointer, such as an arrow or a pointing hand. To highlight a feature with the laser you must overlap it with your extremely bright laser point, completely obscuring the feature as well as readjusting your eye's dynamic range to make the actual features on the slide harder to see. Laser pointer companies pride themselves in outdoing each other with brightness, and audiences are impressed by green laser pointers, the most distracting of all. This is missing the ... "point". When attempting to highlight punctate features the problem finds its ultimate aggravation (and don't get me started when laser pointing on color-merged puncta. Save our souls!). When a laser pointer is activated, its dot is invariably the brightest thing for your eye to look at. In summary, if you use a laser pointer, we in the audience see the laser dot. Not the thing you want us to see.
The laser pointer is the only moving thing in our field of view. Suppose you were looking at a completely stationary picture and something moves in it. We are going to pay attention to the part that moves, not the part that sits still. Otherwise we have to use extreme concentration to suppress our instinct to focus on the stationary medium-intensity background instead of the in-motion brightly colored laser spot. In doing so, we are attempting to suppress an evolved instinct that saved our ancestors' necks countless times. This is another reason why when a presenter uses a laser pointer, we focus on the laser point, not whatever it is he/she is trying to point at.
A laser pointer fosters the detachment of the presenter from the presentation. This is unfortunately the standard presentation mode by the entire community without anyone ever having made a conscious choice about it and has broader sources than just laser pointers. The modern scientific talk has turned into a kind of slide-cast where we all look at the slides and listen to the disembodied voice of the presenter. The two are sporadically connected by a device that projects an unseen beam ending in a bright dot. When a presenter wants to point at a feature, he/she will often step back from the presentation, further increasing the detachment. Is that how you want to learn? From a slide or from a person? Would you be happy if that's how your kids got taught in school? Do you want a talk where the slides are an aid and extension of the presenter, or one in which the presenter's role is to provide commentary on slides? I decided many years ago that scientists are more interesting that powerpoints, so if a presenter forces me to pick between looking at the slides and looking at them (which most do), I always look at them and mostly ignore whatever is projected.
So what are good pointing devices to use?
Your hand. Best pointing device invented. Unlike the laser pointer, you can point at stuff with this, not just on stuff. Walk into your slide if necessary. It is your helper, not the other way around. Stay connected to it.
A stick. Another classic pointing device. It extends your hand nicely to get to some of those plots you put at the top of your slide.
Arrows in the presentation. If you can't do the first two, which may be if you have to talk in an enormous lecture hall and your podium has been unwisely (but commonly) placed far from the projection screens, you can animate an arrow to appear on your slide when you want to call attention to something. This requires you to think beforehand about what you want to call attention to.
What is a good use of a laser pointer? Turns out they make passable lasers for optical applications. You can use them to align your complicated optical experiment, or even do fluorescence microscopy (I've used them for both). It is also apparently the case that the laser dot is very entertaining to cats and they chase after it like it is prey, which coming to think of it is a lot like what we humans do (points 1 and 2 above), so they sell these pointers at pet stores. Unlike humans, though, my brother reports that his cat eventually tired of the novelty.
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