How many characters long can Closed Captions be?

[John Stanowski]

Hey, newb question here.

How long can lines of Closed Captions be?
I’ve adding them to spots for years but I never figured out how “wide” the lines could be.
Or how many characters were permitted in each line.
If you add too many will they get cut off?
Does this text stretch and condense on tv’s?

Help!

2013 Intel MacPro
3.5 GHz 6-Core Intel Xeon E5
64 GB 1866 MHz DDR3 ECC
AMD FirePro D500 3072 MB
Software OS X 10.11.6
Adobe CC

[Brent Marginet]

32 Charaters per line is the maximum but many broadcasters want 26 so none of them get cut off for Standard Def Down Conversions. We always do 26 per line to avoid QC issues.

Pop On is the most common mode for captions and many broadcasters will not accept anything but Pop On. Also stick to a maximum of two lines per caption unless someone is talking so fast that you have no choice but to use three.

You must also stay below 400 Words Per Minute especially for SD, again we always stay below 400 WPM to avoid QC Rejects.

We Caption in MacCaption which allows us to set the maximum line length and also gives error feedback for to many WPM and many other things based on how our Preferences are setup.

Yes they will get cut off because they do not stretch or condense.

I’ve never Captioned in Premiere so I have no idea what its capabilities are.

[John Stanowski]

Thanks so much for answering my question.
For the first time, earlier today, I went all the way to 32 chars. per line.
Previously, I limited the captions to the same width as the text in my lower third which is within the safe zone for SD.
I guess I have to go back to doing it that way now.
Well, at least I know now. thanks!

2013 Intel MacPro
3.5 GHz 6-Core Intel Xeon E5
64 GB 1866 MHz DDR3 ECC
AMD FirePro D500 3072 MB
Software OS X 10.11.6
Adobe CC

[Ken Ellis]

SD captions have a 32 character line length limit. SD decoders will only display captions within Safe Title. If the broadcaster is stretching video so that 4:3 Safe Title content is not visible upon conversion, the length captions aren’t the real problem.