How to design a deck that still works on paper

A projector emits light. Paper reflects it. That one difference explains nearly every way a deck fails when it is printed. White on a screen is the brightest thing in the room, whereas white on paper is only the paper, and the darkest thing an office laser can produce is closer to a very dark grey than to black. The usable contrast range collapses from something like 1000 to 1 down to about 30 to 1, and everything you designed near the edges of that range collapses with it.

The things that break, and what to do instead

Backgrounds, and the toner arithmetic

A dark theme is the most expensive single design decision you can make about a deck that will be printed. A full-page dark background on A4 covers roughly 600 square centimetres in toner. Cartridge yields are quoted against a standard 5 per cent page coverage, and a dark slide runs at 80 or 90 per cent. That is not a modest overrun. You will get a small fraction of the rated page count, and the printer will run slower while doing it, because it has to fuse far more toner into every sheet.

You do not have to redesign anything. Duplicate the deck, apply a light background once in View → Slide Master so it changes on every slide at the same time, and print the duplicate. It takes about a minute, and the printed copy wanted it anyway. If even that is too much, the print dialogue's Pure Black and White setting drops fills to white and keeps text black, which gets most of the way for free. Saving ink when printing goes further into where the toner actually goes.

Type that survives being shrunk

Handouts are usually printed three or six to a sheet, so the slide lands on paper at roughly a third or a quarter of the size you designed it at. An 18 point body line printed six to a sheet is about 5 point on the page, right at the bottom of what most people read comfortably and below what anyone reads in a dim room. The rule is not a font size, it is a ratio: whatever you set, divide it by the number of slides across the sheet and ask whether you would read the result.

• 18 point is the floor for anything you expect to be read, and 24 point is the safe answer.
• Avoid hairline and ultra-light weights. They are designed to look luminous on a backlit screen. On paper they thin out, and on a worn drum they break into dashes.
• Avoid grey body text. Light grey on white loses more contrast in printing than anything else on the slide. Set body text to black and build hierarchy with size and weight instead.
• Be careful with condensed fonts. They shrink better than you expect on width and worse than you expect on legibility, because the counters, the enclosed spaces inside letters such as e and a, fill in with toner.
• Never let colour carry emphasis on its own. Bold survives greyscale, a brand blue does not.

Charts, the worst offender by far

A five-series line chart separated only by colour is the single most common thing in a deck that becomes literally unreadable on paper. Standard chart palettes are chosen for hue separation rather than lightness separation, so a medium blue, a medium green and a medium red convert to greys within a few per cent of one another. The reader can see that there are five lines. They cannot tell which is which, and the legend is no help because the legend is colour too.

• Label the lines directly, at the right-hand end of each line, instead of using a legend. This is better on a projector as well, because it removes a lookup from the audience's job.
• Vary the line style: solid, dashed, dotted. Three styles at two weights gives six distinguishable series using no colour at all.
• For bar charts, vary the fill pattern, or outline some bars instead of filling them.
• For maps and heat scales, use one hue at different lightnesses. A single-hue scale converts to greyscale correctly by definition, because lightness was already doing the work.
• Anyone with red-green colour blindness, roughly one man in twelve, is reading your projected chart the same way the printer is reading it. Fixing this for print fixes it for them.

The things that vanish entirely

• Animated builds. All four bullets appear at once. If the build was holding back an answer, the handout gives it away on the way in.
• Video. A poster frame at best. Write the link on the slide as visible text.
• Hyperlink colour. A blue underlined phrase prints as a grey underlined phrase. If the address matters, spell it out.
• Objects parked off the slide. They do not print, which is convenient, though they are still inside the file and still inside the PDF you send.
• Slide numbers, half the time. Slide numbers live on the slide layout and handout layouts number the sheet instead, so switch both on if anyone will be calling out a number.

A five-minute check before you print thirty copies

1. Switch to View → Grayscale and page through the deck once, full screen, without reading it. You are looking for slides that turn into grey soup.
2. Take the busiest slide and the darkest slide and print those two. On the actual printer, not in the preview: cheap lasers are darker and coarser than any preview suggests.
3. Hold the sheet at arm's length. If you cannot read the body text there, nobody in the third row can read it on the screen either.
4. Convert the finished deck with PowerPoint to PDF so the file that reaches the printer is the one you checked, whatever machine it is printed from.
5. Print one sheet of the handout layout you actually intend to use, at the number of slides per sheet you actually intend to use, and read that before committing the run.

None of this produces a duller deck. A slide that reads on paper also reads at the back of a long room, in a room with the blinds open, and on a phone, which is where a great many decks are actually read. Design for the worst case and the best case comes free. When the deck is ready, print it as handouts rather than one slide to a sheet.

Frequently asked questions