Hi
The text entry window is wider than the VP frame so if you type 39 characters size 10 they will just fit across the frame
(Can't insert image here due to a forum error )
Note that in the text editor window the line of characters only goes halfway across making you think you can add more. This is not the case with this size font
If you type more characters they will appear in the editor window but NOT in the video frame unless you start a new line. If you don't start a new line the text will be truncated and no more characters will appear in the video frame even though they are present in the editor. Using larger characters means you will get less on the editor line, smaller letters more on a line. But don't think that the text EDITOR SCREEN is what you are going to get. Always check with the preview pane. Changing the resolution of the preview in options (keeping the same AR) makes little difference to the preview; perhaps a few pixels at each side as VP (I think) keeps the same text resolution.
If, on the other hand you export at a different AR then the text will be truncated (cropped) it wont be stretched or shrunk to fit.
e.g. If your VP timeline is 16:9 (1.77) and shows 39 characters at size 10 but you export at 704 x 576 (1.22) The text line will now only hold 27 characters. In both cases the VIDEO beneath the text will remain a full frame but in the smaller AR it will be reduced in size at the correct AR to fit......The text will not!
So always export at the AR you have used during editing. Check it looks OK in the sequence preview pane and the text should not get truncated
Nat