The Dictionary Of Photography

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

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Endemann's Process                                                Enlarging
Dr. Eder's Cerate Paste.
Pure white wax Dammar varnish Pure oil of turpentine
... 100 grs. ... 40 mins. ... ico ..
Prepared and used as above described.
Endemann's Process. See Aniline Process.
Engraving Methods, Photographic. See Photogravure, Fish-Glue Process, Galvanography, Daguerreotype (etch-ing of), Obernetter's Process, Electrotyping, Leimtype,
WOODBURYTYPE, CHEMIGRAPHY, ASPHALT PROCESS, TYPES
(originating by photography), etc.
Engravings. Discoloured to bleach for copying. (See Bleaching.)
Enlarging is the operation of obtaining a larger image ot a negative or positive upon some sensitive surface. There are several methods of doing this, either by the use of daylight or artificial light, which will be severally described. But it is first necessary to make a few remarks upon the negative used for this purpose. Sharpness of focus is very necessary, for, supposing a quarter-plate negative taken in the ordinary way is to be enlarged - it may be considered that the discs of confusion appear as points of less thanof an inch in diameter, a point inappreciable to the human eye ; but if these said discs of con-fusion are enlarged, they will become of appreciable size - viz., enlarge a quarter-plate to 12 by 10, or three times, and these discs of confusion will be enlarged in the same ratio ; therefore they will be aboutof an inch in diameter, and will be easily seen. Again, the negative should be plucky, and with good, but not too great, contrasts, and of fair density; in fact, a good silver printing negative will give a good enlargement. For con-venience sake we may divide our apparatus into two classes ; first, that required for daylight enlarging; and, secondly, that required for artificial light. We may again subdivide our two classes into minor sub-classes : thus, daylight enlarging may in-clude (1) Solar work, (2) Diffused light; and artificial light includes (1) Lantern work, including the use of condensers;
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