1. The theory
The PiP window is a 2D duplicate of the cockpit's LCD screen. Both are the same aspect ratio, i.e 4:3 and display the same "video feed".
Ideally the video feed should look exactly the same for all players, on 5:4, 4:3, widescreen or multiple-monitor displays. The PiP camera's FOV should be a fixed value, because the LCD screen and PiP window are always 4:3.
Unfortunately this is not the case.
2. The facts
Here are screenshots of the same "Sling your hook" savegame at various resolutions. Click the previews for larger images.
Note: I deleted all config files and changed my desktop resolution to let the game autodetect the correct aspect every time. This is not a general aspect ratio issue. The HUD is identical on all pictures, only the FOV of the "video feed" is affected.
See the video feed on the PiP window and LCD screen ? The are identical on each screenshot, but don't look the same on any two screenshots. This is because the PiP camera's FOV changes with the game resolution, instead of being always fixed for 4:3, the aspect of the LCD/PiP window.
3840x1024 (3x 5:4)
5760x1080 (3x 16:9)
Here's a closer look at each screenshot's PiP.
Again, they should ALL look like the first one: a 4:3 FOV for a 4:3 cockpit screen, regardless of the actual game aspect.
3. The humble but fervent request
The video feed (PiP and LCD) should look the same in all resolutions, like the PiP window does. So please fix the PiP camera's FOV !