Sources for: It’s hard to read!

All-upper-case captions

Other sources have made the same claims we are making about the origin of all-upper-case captioning.

• Armon, Carl; Glisson, Dan; Goldberg, Larry, “How closed captioning in the U.S. today can become the advanced television captioning system of tomorrow.” SMPTE Journal, July 1992:

  Letters with descenders sit entirely above the baseline, rather than dropping below it, which hampers readability. Accordingly, most captioning agencies use upper case almost exclusively, reserving mixed-case text for sound effects, speaker identification, etc.

• Robson, Gary, The Closed Captioning Handbook, p. 19:

  Captioning in the U.S. [and Canada] has traditionally been done in upper case…. One of the primary factors was the original font for captioning, in which the lower-case letters were difficult to read. There were no true descenders (letters like lower-case y, j, and g were pushed up in the cell to make room for the descender to sit above the baseline) [and] no antialiasing (smoothing of curves and diagonal lines), and the low resolution made it hard to distinguish some of the letters. Today’s character generators in decoders, on the other hand, produce lower-case letters that are quite clear.

Descenderless text is harder to read off a screen

There is some research backing this up.

Treurniet, William C., “Spacing of characters on a television display.” In Processing of Visible Language 2, Kolers, Wrolstad, Bouma, eds. (Plenum Press, 1980):

The test involved looking at a screen filled with random letters. One line was indicated. The subject had to spot the first letter on that indicated line, find the next occurrence of it on the same line, and state the letter to the right of that.

Analysis of frequency of misses showed… an effect due to length of descender…. Analysis of scanning rate in characters per sec showed a significant effect due to…length of descender…. Descender lengths of zero resulted in significantly more misses than descender lengths of one or two pixels. There was, however, no significant difference between the latter two descender lengths. Similarly, the lack of a descender was related to a significantly slower scanning rate than were descender lengths of one or two pixels. Again, there was no significant difference between the latter two descender lengths. These findings suggest that the descender should extend below the line by at least one pixel if it is to be readily noticed.

The reason for the effect of descender length is probably straightforward: A descender that extends below the line by even one pixel is a cue distinctive enough to aid detecting that character accurately.

Movie studio and network that insist on all-capitals captioning

According to private correspondence, Buena Vista is one movie studio that insists on upper case for Line 21 captioning. Although one service provider denies there was ever an order, between 2006 and 2007, prerecorded programming on NBC switched from mixed case to all upper case.