Timelapse of table

I'd suggest you put the camera off to the side a bit rather than
overhead. After all, if you were painting or drawing using an
easel, you'd just put the camera on a tripod positioned behind you
and off to one side. That same kind of perspective ought to work
for desktop work as well.

If you need longer legs on the tripod, well, this is why God made
PVC pipe. Get the size that just accepts the tripod legs, Drill
holes in the pipe at various points, and stick a nail through the
one where you want the tripod leg to bottom out.

Or if you insist on doing the overhead thing, PVC will also be
useful in building whatever scaffold is needed. Not totally rigid,
but ok if you don't bump it, and it will be light and cheap.