Portrait painting by Cornelius Johnson, LeadArt oil painting just do reproduction of them in museum quality on linen canvas:

Cornelis Janssens van Ceulen (also Cornelius Jonson van Ceulen, Cornelius Johnson, Cornelis Jansz. van Ceulen and many other variants) (bapt. October 14, 1593, London – bur. August 5, 1661, Utrecht) was an English painter of portraits of Dutch or Flemish parentage. He has been described as "one of the most gifted and prolific portrait painters practising in England during the 1620s and 1630s".
Janssens' first dated work is 1617, and may be of a Dutch subject; 1619 marks the beginning of his English portraits, which were initially heads only. He was one of the few artists in England at this time who consistently signed and dated their work, except for his later full-lengths, which his clients may have hoped would be mistaken for more expensive Van Dycks. He may have been successful in this, as some full-length portraits attributed to van Dyck's workshop may well be by him. His first identified three-quarter length is dated 1623, and shows a certain lack of skill in dealing with the body, which is overcome in later works. In the early years, his standard way of signing portraits was the phrase “fecit C J”. For painting a portrait, Janssens charged £5. His early portraits were panel paintings with "fictive" oval frames - they appear to have a wooden or marble oval surround, but this is actually painted on to the panel. This “trompe l’oeil” effect was one of Janssens’ favourite devices in the early part of his career. He also painted some portrait miniatures on copper.
He painted many portraits of emerging new gentry, including Lady Rose MacDonnell of Antrim. One of his earliest surviving portraits is of Susanna Temple, grandmother of Sarah, Duchess of Marlborough (Tate). This portrait was subsequently engraved by Robert White towards the end of the seventeenth century. A copy of the engraving was among the prints owned by Samuel Pepys which subsequently passed to Magdalene College, Cambridge. In 1632, Janssens was appointed as a “his Majesty's servant in the quality of Picture drawer” by Charles I, perhaps in connection with the arrival of Van Dyck and the departure from England of Daniel Mytens - Janssens may have been found a role as a back-up for van Dyck. His royal portraits include Charles I as well as Charles II and James II, painted as children, both of which are in the National Portrait Gallery (London). He collaborated with Gerard Houckgeest on a portrait of Charles I's wife, Queen Henrietta Maria.
His style varies considerably over his career, and he was able to assimilate new influences into his own style without any discordant effect. He took from, in turn, Mytens, van Dyck, and William Dobson, and his last Dutch portraits show a different style reflecting contemporary portraiture there.