The Dictionary Of Photography

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

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Autotype Process                                  Auxiliary Exposure
machine contains what may be regarded as a cylindrical and self-luminous negative ; a glass cylinder upon which is wrapped a celluloid negative, containing an incandescent electric lamp. As the band of bromide rolls over this it becomes impressed, and before it leaves the machine it is developed, fixed, washed, and dried. This machine is intended for magazine printing, the text being printed with the pictures, by the type-writer device above mentioned. A single line of characters being brought into order by Mr. Greene's machine, this line is photographed on a roll of film which moves just the depth of a line, when another line is set, and photographed on the same roll of film.
Autotype Process. See Carbon Process.
Aux Deux Crayons. A certain style of stained or toned silver print is or has been known by this expression in the United States. Mr. W. Bell, who advocated this style, says, " Make two solutions, viz.: - No. I. Aloes, powdered, I oz., alcohol 12 ozs •No. 2. Water 12 ozs., liquor ammonise 15 drops. Immerse prints on albumenised paper in No. 1 until they take a bright lemon colour, then wash them well, and put them in solution No. 2. Let them remain until they are a warm orange colour, and again wash them. Mount and touch up the whites with Chinese or any good white, and the blacks with Indian ink. After touching up the whites and blacks, coat the pictures with the following: - Plain collodion 6 ozs., castor-oil 12 drops." A similar proceeding may be carried out with bromide, platino-type, or other prints.
Auxiliary Exposure. It is needless to state that a certain minimum exposure is necessary to obtain any action. When, from certain circumstances, the exposure is too short to allow of the whole of the image, particularly in the shadows, affecting the film, it has been stated that an auxiliary exposure is of great assistance. The auxiliary exposure may be either pre-liminary to or after the real exposure. In the old daguerreo-type days it was sometimes customary to expose the plate, after the real exposure had been given, to the light passing through red or yellow glass, and a more fully exposed image was said to be obtained. With the wet-plate process a similar proceeding was warmly upheld by several, experts. With
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