The left viewport is the regular view that I wanted to convert to an actual camera.
The right viewport is looking through the actual camera.
1st thing I have to do is measure the left viewport and set the scene output resolution X Y to those values.
2nd thing is press ctrl+alt+0 in the right viewport but it looks NOTHING like the left viewport.
3rd thing I have to do is set the focal length of the actual camera to HALF of the focal length reported by the left viewport.
In maya I can just hit render at any time and whatever is in my viewport gets rendered in that exact dimension from that exact viewing angle.
Also you can dig into the outliner’s data api mode to find the exact pixel dimensions of the viewport under “area” but you cannot actual search for the term “area” and find something. You must dig through the tree until you find it.
Window Managers > WinMan > Windows > Window > Screen > Layout > Areas > … and then each editor panel is one of the “Area” items in this list. Open them all until you find one that says “Editor Type: 3D Viewport” with a width and height and x/y position that look like they match the one you’re trying to get.