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Photography. History. The first successful picture was produced in June/July 1827 by Joseph Niépce Combined the “camera obscura” With photochemistry The term "Photography" was first used by Sir John Herschel , in 1839. Camera Obscura. Deguerrotype. Niepce partnered with DeGuerre
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History • The first successful picture was produced in June/July 1827 by Joseph Niépce • Combined the “camera obscura” • With photochemistry • The term "Photography" was first used by Sir John Herschel , in 1839
Deguerrotype • Niepce partnered with DeGuerre • Deguerrotype announced to the public in 1839 • The Deguerrotype was a positive image on a metal plate • One off – no copies • Expensive and long exposure times
Calotype • Invented by Henry Talbot Fox in 1839 • Technique employed was very similar to that still in use today • Negative exposed in the camera, developed in a dark room, and then printed on paper
Glass negative processes • 1848 - Albumen - used egg whites to bind salts to glass plate • 1851 – collodian process – glass plate but much shorter exposure time • Wet collodian process preserved the plates but lengthened exposure time
Gelatin • 1871 - Richard Maddox discovered a way to use gelatin • Used instead of glass as the medium for the photographic plate • Dry plate process • Eliminated the need for portable dark room
Celluloid • First used as photographic medium in the 1860s by John Carbutt • Widely attributed to George Eastman • Eastman introduced flexible “roll film” in 1884 • Eastman introduced the box camera • Called it the “KODAK” • A nonsense word that has no meaning • “You push the button, we do the rest” • Introduced the “Brownie” in 1900
The Brownie $1
Optical Center Focal plane Angle of Acceptance Focal Length In film cameras, 50 millimeter focal length approximates our eyes’ field of vision, or angle of acceptance Depth of Field
Angle of acceptance • Determined by focal length • Long focal length (>50) = “telephoto” • Short focal length (<50) = “wide angle” • Focal length may introduce distortions
Depth of Field • The area where objects will appear to be in focus
Factors Affecting DOF • Focal Length of lens • Longer focal length = shallow DOF • Lens opening • Larger aperture = shallow DOF • Distance to Subject • Closer to subject = shallow DOF • Shutter Speed • Slower shutter speed = shallow DOF
Factors Affecting DOF • Lens opening and shutter speed are determined by light levels • Low light = larger aperture • Low light = slower shutter speed