The Dictionary Of Photography

A True Historic Record Of The Art & Practice Of Photography 100 Years Ago.

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Nephograph
Obernetter's Process
Nephograph. A contrivance for photographing and register-ing the height and position of clouds by photography (by electric release of shutter). Simultaneous exposure being made by two or more cameras at a considerable distance apart, data are ob-tained for the required determination.
New Photography. A term of shifting meaning. A few years ago it meant that class of work in which pictorial effect and excellence is more sought after than mere technical perfec-tion ; five years ago Radiography was frequently referred to as the New Photography. At the time of revising the present edition of the Dictionary, the term " New Photography " has no generally accepted meaning.
Niepceotype. (i) A term sometimes applied to the bitumen process, invented by J. N. Niepce about 1816, and the first method by which a camera picture was obtained. (2) The albumen* process on glass (see p. 12) due, as far as its main features are concerned, to Niepce de St. Victor.
Nitric Acid (Ger., Salpetersdure; Fr., Acide Nitrique). HN03 = 63. Synonym: Aquafortis. Prepared by distillation from Chili saltpetre (nitrate of soda) and sulphuric acid. A heavy liquid fuming in the air. It is extremely corrosive - the antidote being any alkaline earthy carbonate, as chalk, lime, magnesia. (For a table giving the specific gravity of nitric acid of various strengths, see Hydrometers and Hydrometry.)
Nitro-Hydrochloric Acid (Ger., Konigswasser; Fr., Eau regale). Synonym : Aqua regia. A mixture of 3 parts of hydro-chloric acid with 1 part of nitric acid. It is used to dissolve gold for the preparation of gold perchloride, the agent being the chlorine liberated by the interaction of the acids.
Non-Actillic Rays. No rays are absolutely non-actinic, but the term is often applied to the red rays. (See Spectrum.)
Obernetter's Process, or Lichtkupferdruck. A mechanical printing process of very ingenious idea and of extremely pleasing results. The silver image of a gelatine positive is converted into chloride of silver, and the film is then stripped and applied to the surface of a copper plate, and, under the influence of a voltaic current, the silver chloride is decomposed, and the
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