Can't capture entire desktop

[lampshade]

I'm running 26.1.2 on a 2016 MBP (macOS 10.15.7) with 2560x1600 display. I want to capture the entire display but OBS only captures the middle section. Note the gray striped diagonal bars in the image. I've gone through the settings multiple times, there's no cropping or scaling configured. Any ideas?

 

[twindux]

You scale by grabbing the red handles at the corners of your source and resizing the red rectangle to your OBS canvas size.