Other technical details
Infra-red reflectography has revealed small corrections to the under-drawing. We can see some light and rapid lines on the mouth and eyes and in the area of the hands and the outlines of the clothing.
Traces of Dürer’s hand
Visible on the cloak and hands are a number of very fine, dark lines which would be impossible to paint with a brush. They seems to be a final touch applied by the Dürer, who added a thin layer of dark paint onto the painted surface, then put the outer edge of the palm of his hand down onto it several time in order to take off some of the paint, some of which adhered to the tops of these palm-prints.
A flat mirror
In order to paint his Self-portrait, Dürer used a flat mirror which he could have acquired on his first trip to Venice (1494-1495), where it is known that they could be found in the late 15th century. As a result and for the first time the artist was able to completely invert his body and his left arm (which appears to our right) is as visible as the right.