presentationsConsider the lighting conditions

What if I said I had a sim­ple tip that could im­prove al­most any dig­i­tal slide pre­sen­ta­tion? Would that sur­prise you?

And rather than launch into a screed about the dis­mal legacy of Pow­er­Point and Keynote—which is sort of what you were ex­pect­ing from a ty­pog­ra­pher, I’ll bet—what if I just told you the tip?

Be­cause com­plain­ing about dig­i­tal slide pre­sen­ta­tions—it’s been done, right? Like jokes about air­line food. Like “Lean on Me” at high-school grad­u­a­tions. Like air quotes around the phrase mil­i­tary in­tel­li­gence. Like threat­en­ing to move to Canada af­ter the next elec­tion. None of that would sur­prise you.

But a sim­ple and ef­fec­tive ty­pog­ra­phy tip for pre­sen­ta­tions? That might.

So here goes.

As I said in Who is ty­pog­ra­phy for, you should “work hard to see your text as an ac­tual reader will.” With pre­sen­ta­tions, that ad­vice ap­plies on a phys­i­o­log­i­cal level.

Why? Be­cause your read­ers—i.e., the peo­ple in the au­di­ence—will be view­ing your slides un­der com­pletely dif­fer­ent light­ing con­di­tions than you, while you’re writ­ing them. You’re prob­a­bly sit­ting in a well-lit room, look­ing at the slides on a rel­a­tively small lap­top or desk­top screen. To you, the white back­ground you chose for your pre­sen­ta­tion looks pleas­ant and elegant.

But if your au­di­ence is in a dimmed room, their pupils will be di­lated, and their eyes more sen­si­tive to bright light. So when those white slides are pro­jected at epic scale, they’ll just be­come a se­ries of GI­ANT WHITE REC­TAN­GLES float­ing in the air for forty min­utes. Star­ing at GI­ANT WHITE REC­TAN­GLES for that long is painful. It will cost you reader at­ten­tion. Un­der those cir­cum­stances, why should any­one be sur­prised that au­di­ences hate dig­i­tal slide pre­sen­ta­tions? And, ul­ti­mately, the speak­ers who use them?

To be fair, it’s not en­tirely your fault. The de­fault themes pack­aged with pre­sen­ta­tion pro­grams en­cour­age you to pick some­thing bright and kicky. This may help im­prove your pro­duc­tiv­ity and job sat­is­fac­tion. But it will not help your au­di­ence read.

So if your pre­sen­ta­tion will be given in a dark­ened room—here comes the sim­ple tip I promised—op­ti­mize your slides for read­ing in the dark.

  1. Be­fore you start ad­just­ing the ty­pog­ra­phy, put your­self in the read­ing en­vi­ron­ment of your au­di­ence. Turn off the lights and darken your work­space so that the only light is com­ing from your com­puter screen.

    “Whoa! That’s bright!” Now you’re get­ting it.

  2. Then, in your pre­sen­ta­tion pro­gram, start with a black back­ground. Not dark gray, nor a dark gra­di­ent—just black.

  3. You want to get the words on screen us­ing the fewest pho­tons pos­si­ble. So try a thin sans serif font. (Noth­ing wrong with a serif font, but they don’t typ­i­cally come in lighter weights.)

  4. As for font color, pure white type on a black back­ground can have an un­com­fort­able de­gree of con­trast. So start your font at 50% gray and brighten it from there. When it’s leg­i­ble, stop. The thin­ner the font is, the brighter it will need to be.

  5. Pick a base point size that lets you fit 12–15 lines of text on screen. Not that you’ll ever be putting that much on a slide. (I hope.) But that’s a com­fort­able read­ing size. As much as pos­si­ble, use this same point size for every slide—even if there’s only one line of text on screen. Con­stantly chang­ing the point size be­tween slides is annoying.

  6. Be­yond that, the other ty­po­graphic guide­lines ap­ply. In par­tic­u­lar, use color with re­straint—pre­fer pale shades over bright ones. And avoid cen­tered text.

Let’s see how this works in prac­tice. (Click on the im­age to ap­pre­ci­ate it at full size / full horror.)

  1. Gi­ant white rectangle.

  2. Re­ally bad font.

  3. Point size too large.

  4. Line spac­ing too tight.

  5. Cen­tered or­ange headline.

  1. Calm black rectangle.

  2. Bet­ter font (Con­course) in pale gray.

  3. Point size re­duced; line spac­ing increased.

  4. Head­line nei­ther or­ange nor centered.

  5. More “white space” (which in this case is ac­tu­ally black space).

If your pre­sen­ta­tion won’t be given in a dark­ened room, the text-color prob­lem is less ur­gent. Still, you should avoid putting pure black type on a pure white back­ground. Mak­ing the back­ground light gray, or the type dark gray, will re­duce con­trast and im­prove read­ing comfort.

by the way
  • You no­tice the pale gray back­ground of the above slide mostly be­cause here on the web page, it’s sur­rounded with pure white. But when pro­jected un­der or­di­nary light­ing, that pale gray will read as white.

    This is an op­ti­cal phe­nom­e­non known as si­mul­ta­ne­ous con­trast, which you might re­mem­ber from mid­dle-school sci­ence class. For in­stance, in the di­a­gram at left, the cen­ter boxes don’t ap­pear to be the same shade of gray, but they are.

  • Do you re­ally need list bul­lets? Maybe not. In body text, bul­lets make the start of each list item vi­su­ally dis­tinct from the start of a new line or para­graph. But in a pre­sen­ta­tion, if all your pow­er­ful points are less than one line, you can omit the bul­lets (as in the ex­am­ple above).

  • Re­call from max­ims of page lay­out that it’s wise to de­sign out­ward from the text, not in­ward from the page edges. This is rel­e­vant to pre­sen­ta­tions, as the wide as­pect ra­tios of com­puter screens are in­con­ve­nient for ty­pog­ra­phy (and es­pe­cially those of HD-style dis­plays). Feel free to con­fine your pre­sen­ta­tion lay­out to less than the full width of the screen. No one will be both­ered that you didn’t fill the whole space. But be con­sis­tent across all your slides.