Asser here successfully portrayed the children of his beloved sister Netje. The daguerreotype process was so slow that we can hardly imagine what it was like to pose for the camera. The long exposure time is reflected in the sitters’ faces. Their concentrated gaze and every detail seems engraved in the plate, and it is precisely this aspect that makes such photographs so magical. Active children were the most difficult to portray, as their photographs images could blur so easily.