I need to be able to send out a file to around 200 people of a dance concert. i would have liked to have exported it as an mp4 with chapter markers, but apparently adobe doesn't want me to do that. so does anybody know what settings I could use to export a 1920x1080 1hr 40min video with chapter markers and it be under 30gb. so far quicktime using gopro cineform yuv 10bit was the smallest I have got it and that was 85gb final file, which is way too big for purpose.
I wonder if changing your approach might work better? Maybe I'm missing something, but why not just create your video and upload it to a cloud player (YouTube, Vimeo, etc). Then:
it won't matter what size it is, because it will play anywhere
chapter markers are a feature of the player, not the video file (YouTube and Vimeo both let you set chapters, probably others do too)
You can set the privacy so that only the people you want to view it can (Vimeo has much better controls for this)
You can let people download the video from the cloud player (at least I can let people do that with my Vimeo account)
Or maybe a combo of both a cloud link (Dropbox, Google Drive, etc) and a Youtube/Vimeo link would work. The cloud player could be for viewing with chapter markers, and the download link could let people save the file themselves.
Honestly not sure if what you want is possible without some kind of workaround like this. A file format with chapter markers that is also small, for a video that long....? Maybe it's possible....