App Capture mode, exit Full-screen?

[David Faubion]

How do I make OBS capture just the window of only the content of my open, active software--instead of my entire screen? So I want OBS to capture and shoot just the 12" x 6.85" as seen in my attached FRAME TO BE RECORDED image. I know that OBS can do that because I have 94 OBS videos at
my YouTube channel since 2019.

I absently hit CTRL S, and the OBS view went to a full-screen mode. I can't find the default 'window of the app content capture' screen mode.

Please tell me how to get back to the 12" x 6.75" 'record the screen mode'. Thanks for trying to decipher my novice video terminology.

 

[koala]

ctrl-s is the hotkey for stretch source to screen. The function you call with right-click your source->Transform->Stretch to screen.
OBS has a undo function (Edit->Undo). However, if you restarted OBS or didn't use this immediately, it's probably not undoable any more.
You can reset the transform with right click your source->Transform->Reset transform. This reverts the source to the state it was immediately after adding it. You seem to have cropped a part out of it, so for cropping press and hold down the ALT key, then drag the red border handles of the source to the inside to cut what you want to actually capture.

 

[David Faubion]

Thanks, Koala. Based on your general clues, my OBS window stage is now full-width size, 13" up from 12." So that is worth the downtime in fixing it via reset transform and edit transform.