Subtitling "Covington Cross"
When you subtitle a movie, you should follow certain rules so that the subtitles can be read more easily.
Usually, subtitles are displayed in a black box.
You can put up to two lines with 44 characters each into one subtitle.
Make sure that a subtitle is shown no longer than six seconds, but never less than one, and that there are at least four frames between two subtitles, so they are actually readable.
The average time needed to read a line is about three seconds for most people.
When subtitling, two things that are usually true for printed texts do not apply for subtitles:
Proportional fonts are to be preferred over monospace ones, because they take up less space,
and fonts without serifs are to be preferred to those with, because they are easier to read on the TV screen.
Monospace vs. Proportional:
This is an example for a monospace font. (41 characters)
This is an example for a proportional font. (45 characters)
One-liners vs. Two-liners
Generally, one subtitle of two lines is preferable to two one-liners, because then both lines will be displayed longer and are easier to read.
When possible, make the first line of the subtitle shorter than the second one.
When two people are talking in the same subtitle, indicate this by using a separate line for each character and by putting a (-) at the beginning of each line.
When a sentence starts in one subtitle but needs to be continued in the next one, put (...) both at the end of the first subtitle and at the start of the next one.
Do not use punctuation marks only according to grammatical rules, but try to adapt their use to the way people speak in the movie.