Due to the progress of study after the late twentieth century, it is speculated that the Kano family was somehow related to the Nagao clan in Ashikaga, Shimotsuke Province (Ashikaga City, Tochigi Prefecture); and "Waterfall," an ink painting that remains at Chorin-ji Temple in Ashikaga City, is considered a relatively early work by Masanobu.
20世紀後半以降の研究の進展により、狩野家は下野国足利（栃木県足利市）の長尾氏と何らかの関係があったものと推定されており、足利市の長林寺に残る墨画の『観瀑図』は正信の比較的初期の作品と考えられている。