[Robin_Message]

Another cool thing is recovery of picture from ambient reflected light. Sadly it only works on CRTs.

https://www.cl.cam.ac.uk/~mgk25/emsec/optical-faq.html

[fjsolwmv]

You can indirectly photograph any object via its reflectivenes if you have a movable trackable light source and a camera pointed at a wall the object is facing.