MacOS Screen Capture with Application Capture method records whole display area. How-to question?

[DONUSA]

New to OBS. I want to record an application window and nothing else. When I select Screen Capture with method Application Capture, it does just show the application in the video. In my case, the window of the application was sized to only take up about 1/4 of the display. The area of the whole display is also captured, however, and OBS just makes everywhere else on the screen black. When I play the video back, I get the whole display area with just the app window showing in one corner. How do I have OBS just show the app window filling the whole video frame?

 

[mishakim]

What application are you using? My first guess would be that something about the app isn't communicating its window size properly.
At any rate, the Application Capture method isn't very useful anyway, it loses track of which app it's targeting if anything changes. Instead, under the "deprecated" sub-menu of the source list, choose Window Capture