I have tried to make subtitles for a video with subtitle editors. I have tried several: Subtitle Composer, Gnome Subtitles, Gaupol, Subtitle Editor and Aegisub.
I found the experience horrible. It was almost impossible to achieve anything. Consulting websites and watching Youtube videos on the subject didn’t help. It has taken me more or less a day before I understood how to do it. This is mostly caused by the bad interface of
these programs. Nevertheless, once you have understood it, you can achieve great results.
I found Gnome Subtitles to be the best program. This program excels by its simplicity. And it therefore easy to use (once you have understood it).
The most surprising program was Subtitle Editor. Once you have understood the interface (and that takes time), the program offers you a few interesting extras. First of all, it is possible to import text files. These will be automatically converted to .srt files (subtitle format). A feature that Gnome Subtitles not have. The program has no buttons with which to control it. Instead you can make socalled keyboard shortkeys. When you have to create subtitles only once, it is too much work. But when you have to do that more often, this feature is most helpful.
The program Aegisub is the most elaborate of all the programs that I have tried. Someone who is already familiar with audio software, will comprehend this program quite easily. It offers you the possibility to format your text (italic, bold, color etc. etc.). For those who will make subtitles more than once, this will probably be the program you end up working with.
Gaupol doesn’t have the feature to program certain keys of your keyboard. That means that you have to use the mouse to control your program. Eventually, this is too much a drawback to me.
Subtitle Composer is a good program but without the many extras which Subtitle Editor has. I therefore choose for Subtitle Editor.
But how do you make subtitles? This you do by delaying the video. This offers you the time to add the text at the right place.
A last remark: in may editors you must use Insert (after) when you want to add a subtitle.