estorers spend a great deal of time working with stereo microscopes, usually attached to an extendable arm with tilting capabilities. Examination of the whole surface area of the painting under a stereo microscope is necessary to avoid missing valuable information invisible to the naked eye regarding the condition of the paint, varnish and support.
Specific attention is given to the nature of the craquelure of the paint layer, the condition of the tears and cracks as well as the spread of previously applied retouchings and overpaintings. Most importantly, though, the microscope is used during complicated restoration procedures such as thread-by-thread tear mending and varnish removals. The picture on the left shows how under a magnification of 10 times, it is possible to align threads on opposite sides of a tear.