Rate at which AC initially moves to point at an ROI?

What tells AC how fast to yaw and and how fast to pitch the gimbal when it executes a DO_SET_ROI in a mission? It seems to be a rather abrupt move to align the copter yaw and gimbal pitch with the ROI. It is nice and smooth once it’s there and tracking the ROI. It’s just the initial swinging into position I’m curious about. If there is a parameter I can adjust to slow/smooth that out, that would be great. But I have a feeling whatever I do to slow that down will adversely affect normal flight too.