Welcome to TVPaint Community forums !

I am trying to export a scene with the JSON export option (to take it to After Effects) .

How long is considered "normal" for the export of a large scene ? Should I be waiting an hour or more for a scene to export ? I've got a scene that is 4k resolution, 757 frames, 22 visible layers ... I know this is large , but is the JSON script not usable above a certain size ? The export gets to 9% and then sticks there for a long time . Then I check on 30 minutes later (still stuck at 9%) and it says "TVPaint 11 Not Responding" (app is frozen) . Check again at the 1 hour mark and it is still stuck at 9% . Sometimes with other scenes I've had that happen , but if I wait a while TVPaint will "unfreeze" itself and finish the export , but in this case it never gets unfrozen, so I have to do a Force Quit.

Well, if it really exports each layer separately in each frame this will add up to 16.600 images, at a rate of 1 image per second you'll need 5 hrs to save.

The calculation makes perfect sense , what I'm worried about is the progress bar getting stuck at 9% for over an hour and the application TVPaint shown in the Finder Force Quit list as
"TVPaint 11 Not Responding" . If it only advanced a little bit every 30 minutes or so and the app didn't show as frozen , I'd be ok with just leaving it to export overnight, But I'm afraid what I'll find in the morning is the progress bar still stuck at 9% .

Well, that's one of TVP's habits: it isn't really responsive once it focuses on something. System calls every time and then, but TVP doesn't get itself distracted from the task at hand, so System marks it as "unresponsive" which is perfectly true. I wouldn't mind if it would at least allow for "hide program", but even this may take minutes. Screen refreshs suffer as well, that's why you don't really see any progress at the bar.

I'd say give it a try, 5 hrs rendering at night are not that bad. I think I never had anything rendering longer than 2 hrs, but it always worked (from any software).

My latest attempt at the JSON export has been running for a bit more than 2 hours at this point and when I checked it again about 10 minutes ago was pleased to see the progress has now jumped to 65% completed !

So maybe it's not so bad as I thought . And checking again just now I see it has jumped to 82% in the last couple of minutes .

TVPaint still shows in the Finder as "not responding" , but it's obviously not frozen as I had feared , it seems to be just chugging along at it's task , ignoring the System calls , as you said .

It finished in about 2 hours and 45 minutes. So I just needed to be more patient ...

There's a nice little utility on Mac, "Activity monitor" (?), I've put it in the dock, you can have the icon show the recent CPU activity. If there's a flatline (on all cores) for some time you can be quite sure TVP has stopped working, otherwise it's still doing something.

Yes, I have also noticed that the JSON export overestimates the time remaining, often looks like it's not going to work, but almost always comes through.
I'll recommend another cool macOS (Mojave-compatible) tool, free monitoring of CPU,disk,RAM, and network activity in the menu bar, highly customizable: MenuMeters: https://member.ipmu.jp/yuji.tachikawa/M ... ElCapitan/