And, just for grins, let's try out Derrel's experiment!
85mm lens, shooting at f/2.0 on a FF body, from a distance of 12' from the subject.
Distance to very top or bottom edge of the frame is about 12' 3" and if you focus there you run out of DoF at 11' 11" more or less. So when you swing to center up, your subject is juuuust barely inside the acceptable DoF, by 1 inch. This is a swing of about 12 degrees, you'll find it about two hand widths, more or less, which I think I established is in the range of "uh oh" and constitutes swinging the camera around wildly. Use a more appropriate focusing method, rather than focusing on the subject's eyes with the center focus point, and the recomposing to center her navel in the frame.