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Typography

The Polarity Penalty

·7 min in full, in the book·PagePerfect Journal

The figure that made this essay was a zero: good comprehension at 70 per cent for black on white, and 0 per cent for the same text reversed.1 No other measurement cited here produces one. What the controlled work produces is a cost with a size: about a tenth of reading speed on paper, and a measured advantage for the light ground in acuity and proofreading on screen.23 A cost can be weighed against the reasons a reader might want a dark ground. A death notice cannot.

The rest of this essay is in the book

It goes on to cover:

  • Where the zero comes from
  • The penalty on paper
  • Screens are not paper
  • Where irradiation stops
  • Ink spread, and the sizes printers ask for
  • The reader who chose the dark theme
  • Where a dark ground earns its place

About the book

Notes

  1. Cutting Edge PR n.d., Table of the serif results: black on white 70/19/11; white on black 0/12/88; white on PMS 259 2/16/82; white on PMS 286 0/4/96; Open Library full-text search, Type & Layout, Full-text search of the 1995 book: no snippet containing the reversed-serif table. The serif table could not be traced to a primary source. The figures sit consistently with the report’s other numbers and are almost certainly its author’s, but as cited here they rest on a secondary account of the 1995 book. A zero given without variance is a reason to look at the method. Evidence C: professional practice or tradition.
  2. Tinker 1963, Ch. 9, Table 9.1 (280 readers; white on black 10.5 per cent slower; reader opinion 77.7 / 22.3) and Table 9.2 (Taylor eye-movement study); Ch. 11 (14.5 per cent in a 44-pica line; about 18.5 per cent set solid). Speed-of-reading tests on printed material, mid-twentieth century, the two settings printed as zinc etchings on the same enamel stock. Tinker records no accommodation effect and no fatigue measure for reversed type; the 22.3 per cent figure is a preference judgement. Evidence A: strong or direct evidence.
  3. Piepenbrock et al. 2013, Abstract; section 2.1 Participants (85 older, 84 younger); section 3.1 Results, visual acuity, F(1,163) = 69.31, p < 0.01. Older adults 60 to 85 (mean 69.8) and younger adults 18 to 33 (mean 22.6), on displays. Ambient lighting and character size were not varied in this study, and the advantage was smaller for the older group. Evidence A: strong or direct evidence.

Sources

  • Cutting Edge PR. Reverse typeface can dramatically reduce readability. cuttingedgepr.com
  • Open Library search-inside, Wheildon 'Type & layout' (identifier typelayouthowtyp0000whei). openlibrary.org
  • Tinker, M. A. (1963). Legibility of Print. Ames: Iowa State University Press. gwern.net
  • Piepenbrock, C., Mayr, S., Mund, I. & Buchner, A. (2013). Positive display polarity is advantageous for both younger and older adults. Ergonomics, 56(7), 1116-1124. doi.org

Further reading