Roux-Lavergne entrusted Besson to
François Souchon for instruction in drawing. At the start of 1833, when Besson was just seventeen, he was able to work with Souchon on a portrait of the Abbé Leclair that was exhibited at the
Salon that year. It has since been lost. On 17 March 1833 the priest died and left a generous bequest which gave the mother and son financial freedom. Besson and his mother moved to the Rue de la Monnaie. Besson left school but continued to study under Souchon. Towards the end of June 1833 Souchon invited his pupil to accompany him and
Xavier Sigalon to Italy to help prepare a copy of
Michelangelo's painting of
The Last Judgement in the
Sistine Chapel. The stay in Rome was short-lived. On returning, Souchon advised him to take lessons from
Paul Delaroche. Besson did not enrol at the
Ecole des Beaux-Arts. Delaroche gave him some advice, and encouraged him to copy the masterpieces of the Louvre. He gave a copy of Titien's "The Entombment" to the Abbé Desgenettes. This meeting marked the start of his conversion. In the fall of 1838 the Bessons, mother and son, left for Rome. Besson had a studio on the corner of Via Felice and Via della Purifazzione, which he shared with the landscape painter
Louis-Nicolas Cabat (1812–1893). While in Italy Besson took the opportunity of studying the paintings of the masters. He wandered in the streets of Rome and the surrounding countryside, making many sketches of the people and landscapes. He joined a small group of like-minded Catholic French artists. In the summer of 1839 Besson, Cabat and a few friends went on a sketching tour to
Lake Albano,
Ariccia,
Civita Castellana and
Foligno. Besson then went on alone to
Assisi. In Lent of 1840 he stayed at the monastery of La Quercia, where he made a copy of the 15th century
Madone de la Quercia. After finishing this work he decided to become a priest, and obtained his mother's reluctant assent. ==Priest==