Manson began to paint seriously in the early seventies and displayed a liking for the traditional Irish landscape, particularly the rugged mountains and the coast and lake views of the west of Ireland. He has long admired the works of past Irish landscape artists such as J H Craig, Frank McKelvey and Maurice Wilks. The inspiration for much of his work is found in Mayo, Galway and Donegal.

Since 1980 he has exhibited in many galleries in Ireland, and his work is in numerous private collections throughout Europe. He has now joined the Waldock Gallery panel of artists.