— First photographic compound portrait lens made by Andrew Ross, London.
— Towson, of Liverpool, noted that chemical and visual foci did not coincide. Defect corrected by J. Petzval, of Vienna, for Voightlander.
— “A Popular Treatise on the Art of Photography, including Daguerreotype and all the New Methods of Producing Pictures by the Chemical Agency of Light,” by Robert Hunt, published by R. Griffin, Glasgow.
— Daguerre announced an instantaneous process, but it was not successful.
1842. Sir John Herschel exhibited blue, red, and purple photographs at the Royal Institution.
— “Photography Familiarly Explained,” by W. R. Baxter, London.
1843. “Photogenic Manipulation,” by G. T. Fisher Knight, Foster Lane.
— Treatise on Photography by N. P. Lerebours, translated by J. Egerton.
1844. Fox Talbot issued “The Pencil of Nature,” a book of silver prints from calotype negatives.
— C. Cundell, of London, employed and published the use of bromide of potassium in the calotype process.