A skilled engraver, his works have provided historians with invaluable information regarding the appearance of many of Norwich's streets and medieval, Tudor and Georgian buildings prior to their demolition.

[11] The surname Ninham originates either from the Middle English innom ('enclosed ground'), or from an unidentified minor placename in southern England, such as Inholmes, in Sussex.

[12] The art historian William Dickes, writing in 1905, believed Henry Ninham's grandfather was a Huguenot who came to England from Flanders following the revocation of the 1598 Edict of Nantes in 1685.

He lived and worked at 11, Chapel Field, where he specialised in painting coach panels, in common with his contemporary John Crome.

His Beach Scene, painted in the 1760s, is considered by the historian Andrew Moore to have been important in establishing his artistic style.

The drawings, produced using a camera obscura, are of interest to historians as they were made just before the gates were demolished by the city authorities.

[24] He trained under his father as an apprentice engraver and a heraldic painter,[25][13] and was taught art by John Crome, who influenced his use of soft greys and pinks in his palette.

[26] As a skilled engraver Ninham was capable, according to the author William Dickes, of producing a miniature image of a peacock that was so detailed that individual feathers could be seen with the aid of a magnifying glass.

[29][13] One drawing he produced, of Sir Benjamin Wrench's Court (an etching now with Norfolk Museums Collections), is of importance for depicting the location of the Norwich Society of Artists' exhibitions from 1803 to 1825.

[37] Daniell was licensed in 1832 as the curate of Banham,[38] and lived there until in 1834 he was appointed to the curacy of St. Mark's, North Audley Street in London.

[47][6][48] Ninham had pupils, including the landscape painter Alfred Priest, whose early works were strongly influenced by his teacher.

The family employed a servant, Susan Bangay (born around 1831), who lived with the Ninhams for over twenty years, and who supported Henry in his old age.

[25] His works only attracted occasional interest in the local press, for instance when he was noted for his accurate and precise draughtsmanship by the Norwich Mercury, in an article dated 14 August 1824, which praised the "neat delineation" of his engravings.

[6] Following the announcement of his death in 1874, the Norfolk News wrote: "Mr. Ninham was at all times ready to impart his knowledge to others, and his kind and genial manner will, apart from his artistic abilities, cause him to be long remembered by all who had the pleasure of his acquaintance".

They sometimes etched the same buildings, as with the now demolished Sir Benjamin Wrenches Court, but Hodgson tended to be more interested in depicting ruins than his contemporary.

[57] Their views of Norwich have provided historians with a valuable and accurate record of the city's streets, as many buildings that they knew have since disappeared.

[60][61] In 1937 the artist John Moray-Smith produced seven murals for display on the sides of pubs, each depicting one of the city's gates and closely following engravings by Ninham.