Had a go at creating an Apple style animation for fun…
Ignore the snow filter that was added in post
Had some trouble trying to use the camera keyframe animation look smooth changing the perspective. I got a zoom out when when what I wanted to achieve was the camera staying (or appearing to stay) the same distance/zoom away from the projector, but the perspective changing to move of an orthographic style (I think it was set as orthographic as it could go within the perspective)
Harry, when doing focal length change animation, if you want the perception of object not zooming out, then simultaneously you should do a camera dolly animation with distance of dolly travel equal to the change in focal length.
So if you start with 200mm focal length and linearly change it to 100mm over 1 second,
Then add a dolly animation (dolly in) with distance of 200-100 = 100mm over 1 second!
Hope that helps