Adding and editing a zoom
Adding one
Put the playhead where the zoom should be and press Z, or open the Zoom tab with nothing selected and press Add zoom clip at playhead.
A new clip appears on the Zoom track. Drag its ends for how long it lasts, and drag the whole clip to move it.
Settings on a zoom
Select the clip and use the Zoom tab.
Zoom level is how far in it goes, from 1.2 times up to 4 times.
Zoom mode is Auto or Manual. Auto keeps the mouse pointer in the frame and follows it. Manual aims at a fixed part of the picture that you choose, by dragging on the preview or with the two sliders under CENTRE. Use Manual when the interesting thing is not where the mouse was: a notification in a corner, a number in a table, a form field somebody tabbed into.
Glide is off, slow, medium or fast, and it is how much the camera drifts after the pointer while it is zoomed in. Slow reads as a hand held shot. Off holds perfectly still.
Disable zoom switches this one clip off without deleting it, which is handy when you are deciding.
Set as default takes this clip's level and makes it the level new zooms get. The Default level control on the same tab with nothing selected does the same thing directly.
How the picture moves
With nothing selected, the Motion tab has the movement settings for every zoom in the project.
Tension, Friction and Mass are the three terms of a spring, and they drive the zoom camera the way they drive the pointer. More tension arrives faster. More friction settles without overshooting. More mass is heavier and slower to change direction. The defaults are tuned to look deliberate rather than nervous, and they are worth leaving alone until something specific bothers you.
Lead in is how long before the clip the camera starts moving, so it has arrived by the time the clip begins rather than still travelling while the thing you wanted to show is happening.
Screen zooming in and Screen moving are motion blur while the picture changes. The preview shows screen blur on a paused frame and skips it during playback to keep the preview smooth; the export has it.