So I had researched it a while ago and don’t recall having found anything effective and non-suspicious to protect from public camera mass survaillence in cities and the like. Is there anything that is a good option for that yet, and if so, could you point me toward it?
Yes that makes sense, the range finding sensor from an old cell phone should do nicely.
You can 3d print a geared lens barrel for small M12 lens quite easily.
Just map the values to real gear position and bingo’s your uncle !