Beats me. I don't even know where you got that info; maybe in System Info...? If I open FT, I get a square window with a list of people along the left and a 'portrat' image of myself in the main view. I can't remember the last time I used FT, so I don't remember what happens when one actually connects with a person or even 4. I do assume that's where you are seeing a 16::9 image. Sitting ~24 inches from the camera, I can't even see my complete shoulder width. If anything, the simple start up image is 9::16; a vertical rectangle, not like the regular screen at all.
Hopefully, some one will come along and 'splain thangs!!!
Perhaps I can connect with SWMBO or my GD... That thing runs on iPads, right? How 'bout I screen share my wife's MBP and set up FT on it...
Hhmmm... First I got her on her iPhone and nothing happened to my window; it's still the vertical image of me. I figured her phone might be limiting the image to that vertical display, so I screen-shared to her MBP.
Same thing, a vertical image. But, since she wasn't in front of the machine, I did get a view of the opposite side of the room.
Is that what you're talking about; too much background stuff and not enough people view?If so, I think the only solution is to sit closer to the camera. Maybe a dose or two of Retinol or Botox to blur out any wrinkles, should you have any! I can't see any way to improve my appearance except with some tape over the lens!!
I did try changing the "Scale" in System Pref->Displays, but it didn't change the image dimensions/ratio. BTW, I'm running the same OS on the same size iMac.
I see some buttons/controls in FT Help, "Change your view of a call" that don't appear in my iMac window. My wife's iPhone did have some of those buttons, however. Clicking the green window button does make the image/window re-size to the maximum vertical screen size, but it retains the 'portrait' layout.
Good luck, young Will Robinson!
"Oh, the pain ... the pain!"