Difficulties in subtitling foreign language material

In the French language movie Queen To Play (2009), there is a sequence where characters recite chess moves.  One of those moves is Black's bishop to the g4 square, which is mistakenly subtitled "Bishop...j4", an impossible move.

To me that's a strong indication that the person doing the subtitles was not a native French speaker, and also did not know the algebraic notation of chess.  The sound of the French letter g is somewhat like the sound of the English letter j, so someone who was more used to English than French could easily have mistakenly chosen j, particularly if they didn't know that the algebraic notation letters for a square on the chessboard range only between a and h.  A native French speaker, however, is unlikely to write j if they have heard g, even if they knew nothing about chess algebraic notation.

In the French language movie Amélie (2001), one character is directing another character over the phone to a certain page in a book. The spoken French is "Page 51.", but the subtitle says "Page St.". That error seems like someone misread handwriting for 51 as St. I see now that this error (and others) are cited for this film at IMDB, under Goofs > Audio/visual unsynchronized, although my interest is more about the aspects of language underlying such errors, not the errors per se.

Subtitles in pirated works probably take even more of a beating.

In the movie Tape (2001), one character responds to another's question about what time it is with "It's quarter of.", without specifying the hour (i.e., quarter of what). The subtitle is "十五分" (15 minutes). There is no Chinese translation for "quarter of" if the hour is not specified, so this inaccurate subtitle is no surprise.

In Star Wars: Episode I - The Phantom Menace (1999), a character says "They went down the ventilation shaft!". According to my memory, a pirated Chinese version used the subtitle "他们出去了" (simplified Chinese for "They went out!"), which lacks the flavor of the original sentence.


11/15/12: Translators rendering subtitles are always under text length limitations, and may be forced to make compromises. For example, not all languages have a single word for "siblings", as English does, and the character count is clearly higher for "brothers and sisters".