Photographic Flashcards
Photography came from the Greek word:
- PHOTOS which means “light”
- GRAPHOS which mean “drawing”
Overall, it means “Drawing by Light”
is the most common method humans have at receiving and conveying impressions of the world they exist in.
vision
The first recorded use of HISTORICAL LENS was used for
image formation
discovered the fixing properties of thiosulfate, paving the way for permanent pictorial productions
John Herschel
The year John Hershel discovered the fixing properties of thiosulfate, paving the way for permanent pictorial productions
1819
The year Archer improved and perfected the “WET-COLLODION
PROCESS”
1851
discovered the SUPERIOR GELLATIN process, which had been preferred by the public.
Maddox
The year the first exhibit with photographs was done.
1839
made the first photographic portrait
Dorothy Catherine Draper
discovered that dye molecules absorbed on the silver haldes crystals greatly increased the light sensitivity of these crystals
Vogel
introduced TRANSPARENT
ROLL FILM and popularized the SNAP SHOT
George Eastman
sucessfully reproduced images as negatives on papers impregnated with silver salts. Soon after this, practical methods for producing motion pictures were invented
Thomas Wedgewood
The year Hoescht Dye Works in Germany used color-sentisized emulsions.
1904
Velox developing paper was discovered by
Leo H. Baekland
The year Wratten panchromatic plates were introduced.
1906
The year Portrait Film was introduced and at the same time, Projection Printing came into general use
1920
the year natural color film amateur color prints were introduced respectively
1928 & 1941
Amateur use of Photography involves in 3 Major ways:
prints
home movies
small transparency
PROFESSIONAL USE OF PHOTOGRAPHY
Entertainment
Education
Sales
Graphic Reproduction in Magazines
Display Advertising
Data Recording
Nondestructive Testing
Medical and Scientific Records
is the process of producing image by the action of
light or other radiant energy.
PHOTOGRAPHY
are included as initiators in photography
ULTRAVIOLET and INFRARED LIGHT
In the case of economically significant photographic
processes, the “Light” sensitive substances employed are:
SILVER HALIDES
DIAZO COMPOUNDS
AMORPHOUS SELENIUM
ORGANIC PHOTOCONDUCTORS
ZINC OXIDES
are widely used for medical use, x-rays, graphical arts, and engineering drawings but are slower compared with SILVER HALLIDE films.
SILVERLESS FILMS
- a new development that threatens to take over some of silver film market
- uses VIDEOTAPE instead of FILM to produce image
ELECTRONIC CAMERA
• employed as the sensitive substance in most widely used photographic products
• has natural sensitivity to ultraviolet and blue radiation
• Their sensitivity to Red, Green, and Infrared is Negligible unless sensitization to the regions is induced by adsorption of sensitizing dyes.
SILVER HALIDES
consists essentially of an emulsion on a film support of cellulose acetate, polyster, or glass
films and plates
• composed of suspension of minute silver halide crystals in gelatin
• suitably sensitized by the addition of certain dyes
• antifogging agents, hardening agents
emulsion
fogging of the emulsion by light reflected into it from the back surface of the film
halation
Its function is to chemically reduce the silver halide to metallic silver in various points where light has produced the latent image.
Reducing Agent
Its function is to guard the developer against air oxidation.
Preservatives
Its function is to increase the alkalinity of the developing solution, hence increase the activity of
most of the developing or reducing agents.
Accelerators
Its function is to control the speed of the developer.
Restrainer
is based upon the principles that the colors of nature can be adequately represented to the eye and brain by mixtures of BLUE, GREEN, and RED LIGHT.
COLOR PHOTOGRAPHY
The use of Blue, Green, Re beams or filters is dificult and wasteful of lightful energy. Most methods are based on compliments of blue, red, and green, which are
YELLOW, MAGENTA, and CYAN
yellow, magenta, cyan controlls what colors
YELLOW FILTER - controls blue ; permits green and red
MAGENTA FILTER - controls green ; permits blue and red
CYAN FILTER - controls red ; permits blue and green
Dyes with properties suitable for color photography are produced when the development is accomplished by p-phenylenediamines in the presence of an active species called
Coupler
Preparation of light-sensitive emulsion
• Silver halides are sensitive only to
wavelengths shorter than 500 nm.
• Orthochromatic Emulsion- sensitivity is increased to 600 nm.
• Panchromatic Emulsion- sensitivity is
increased to 700 nm.
Manufacture of the
base or support for
the emulsion
Glass- precision photography
Plastic- Modern photography
Paper- print materials
Coating of the emulsion
on the base
• The finished product consists of several separately applied emulsion layers.
• Intermediate layer is used to prevent stray
light from reflecting back.
• Color Films requires many layers of
emulsion.
absorbs most of the light that would
otherwise be reflected back up
through the emulsion, scattering the
light and reducing sharpness in the image.
Gelatin Anti-Halation Layer
prevent the tendency of the
film to curl when the emulsion
swells during processing.
Anti-Curl Backing
solid sheets of thermoplastic or partially
cured (B-staged) thermosetting polymers
that can be cut to size and generally used
to attach large-area components,
substrates, and lids.
Adhesion Promotion Layer
a thermosetting resins with high
cohesive strength and excellent adhesion
to metals, ceramics, glass, rubber, and
some plastics. They are generally rigid
and have excellent chemical resistance.
Epoxy film enables clean, consistent bond lines and manufacturing that
eliminates dispensing of liquids.
B-Stage Epoxy Film
the layer of plastic that
supports the images, sound,
and other information
contained in the emulsion.
Film Base
holds something in suspension. It is this
material in suspension that is sensitive to
radiation and forms the latent image on the
film.
Emulsion Layer
protecting the film from scratches during handling.
Gelatin Protective Coating
Black and White Film Layers
Gelatin Anti-Halation Layer
Anti-Curl Backing
Adhesion Promotion Layer
Film Base
Adhesion Promotion Layer
Emulsion Layer
Gelatin Protective Coating
Special Applications of Photography
• PHOTOMECHANICAL
REPRODUCTION FOR ILLUSTRATIONS
• PHOTOCOPYING
• MICROFILMING
Classification of Ink
Printing Processes
Relief Printing
Intaglio Printing
Planographic Printing
• also referred to as PHOTOENGRAVING.
• the raised portion of a plate
receives the ink for transference to
the paper.
• LINE PLATES and HALFTONE PLATES are
used.
Relief Printing
• includes PHOTOGRAVURE, ROTOGRAVURE,
and METAL ENGRAVING.
• reverse of the relief printing
procedure.
• the hollow regions of the plate or
metal cylinder hold the tank.
Intaglio Printing
• also known as LITHOGRAPHY.
• makes use of the inability of a
water-wet surface to the tank.
•utilizes lithographic plates which
are particularly adaptable to
illustrative work in color.
Planographic Printing
• uses photosensitive acrylic plastics bonded to metal.
• marketed in 1960.
Dyeril Photopolymer Printing Plates
• formed by the light-induced cross-linking of nylon has been described in the literature.
Photopolymer Printing Plate
first successful use of color to
create a three-dimensional effect
on a flat surface.
Panography
PRINTING-OUT PROCESS
Silver Process
Chromate Process
Iron Process
• Herschel, 1842.
• a method dependent on the ability
of the ferric ions to be reduced
to ferrous ions.
• cyanotype (positive blueprint)
Blueprint process
the first successful
document copying device not requiring
especially prepared originals,
invented in 1900.
Rectigraph
• the beginning of the revolution in
copying methods.
• image-forming process which
creates essentially full-sized
copies of the original.
Diffusion-transfer Reversal Process
most widely used photocopying technique invented by the Xerox Company in 1937.
Electrostatic Process
uses an electrically-charged zinc
oxide-coated paper.
Electrofax
• the art of making miniature photographs facsimliles of original material.
• brought revolution in microforms
Microphotography
has a reduction of 12-22
diameter of the original.
microfilms
name applied to single-sheet forms of microfilms.
microfiche
used for positive
copies.
Kalvar film
stabilizes the
compound and the air sacs.
ultraviolet light
In US, what is the biggest photography product purchase?
Amateurs
A process wherein it removes silver halides.
fixer bath
Louis Daguerre (Frenchman)
released his formula to manufacture a familiar
_____
daguerreotype
