Otto Flechtenmacher was a painter who lived in Austria, an uncle of Christa. I often did photography for documentary purposes, especially paintings.
This morning I listened to a workshop of portrait photography. To some extend the audience received explanations of the PhaseOne camera, which I use quite frequently. The vast dynamic range and the frame averaging feature of a PhaseOne were mentioned.
To reproduce these features I intentionally underexposed a photo of a painting of Otto. The original histogram can be seen on the left, the processed one on the right. The quality is quite surprising, when you are used to full frame sensors.