lens, as differentiated from the focal plane or
behind-the-lens shutters. Sometimes applied to an
iris diaphragm whose blades operate between lens
elements.
SHUTTER, FOCAL-PLANE–A shutter located near
the focal plane and consisting of a curtain with a slot
that is pulled across the focal plane to make the
exposure. The width of the slit and the speed it is
moved determine the duration of the exposure.
SHUTTER RELEASE–A device to actuate a camera
shutter.
SHUTTER SPEED–The length of time that light is
permitted to act upon film or paper as a result of the
shutter having opened and closed.
SILHOUETTE –An art term for the outline of a form
in black or white that is offset by a background of
the contrasting color. (PIA)
SILVER HALIDE–A compound of silver and one of
the following elements known as halogens:
chlorine, bromide, iodine, and fluorine. (NMA)
SLANT TRACK–Same as helical scan.
SODIUM HYDROXIDE (CAUSTIC SODA,
SODIUM HYDRATE), NaOH–A deliquescent
white material usually available as pellets, flakes,
or sticks. Soluble in water with the liberation of heat.
A very active accelerator used in high-energy
developers. Concentrated solutions are quite caustic
and will attack the skin, causing painful burns.
SODIUM THIOSULFATE (THIOSULFATE OF
SODA, HYPO) Na2S2O35H2O–Colorless crystals,
very soluble in water. It is the principal constituent
of most fixing solutions. It may be available in the
anhydrous form.
SOFT–(l) As applied to a photographic emulsion or
developer, having a low contrast. (2) As applied to
the lighting of a set, diffuse, giving a flat scene in
which the brightness difference between highlights
and shadows is small.
SOFT FOCUS–An unsharp photographic image or a
special lens or exposing technique by means of
which it is produced. (PIA)
SPECIFIC GRAVITY (LIQUID AND SOLID)–The
ratio of the weight of a substance to the weight of
an equal volume of distilled water.
SPECULAR –Like a mirror, reflecting in a regular
manner so that clear images may be formed,
nondiffusing.
SPOT–A contraction of “spotlight”; a lamp which
projects a narrow, strong beam of light. (Verb) To
remove spots from photographic prints, sometimes
called "positive retouching" or"print retouching."
SQUEEGEE–(l) A rubber blade mounted in a holder
which, when drawn over the surface of a wet film
or paper, removes the surface liquid. (2) Rollers
used for the same purpose. (3) On continuous
processing machines, air squeegees may be used
that remove surface liquid by either suction or by
blowing air against material being processed.
STAIN–A local or general discoloration of negatives
and prints.
STEP TEST–(l) A series of exposures made with
gradual increases in illumination used to determine
proper exposure conditions. (2) To test for contrast
or latitude, you can use a step wedge in a single
exposure. (NMA)
STOP BATH–A stop bath is an acid solution used to
arrest development by neutralizing the alkaline
developer with which the photographic material is
saturated as it leaves the developing bath.
STROBE–Designates an electronic flash lamp.
SUBTRACTIVE PRIMARIES–The three printing
colors used in three-color subtractive color
processes:
magenta (minus green), cyan (minus
red), and yellow (minus blue-violet). (PIA)
SYNCHROFLASH –Photographic arrangement
whereby a photoflash lamp is timed to provide
illumination at the instant when the camera shutter
is wide open.
TIME BASE CORRECTOR (TBC)–An electronic
accessory to a videotape recorder that helps make
playbacks or transfers electronically stable. A TBC
helps to maintain picture stability even in
dubbing-up operations.
TIME TEMPERATURE CHART–A table showing
the optimum time of development at the standard
temperature for various photographic materials in a
given developer or for different times of
development in order to obtain equivalent
development at nonstandard temperatures. (PIA)
TONE–(l) In a photographic negative or print, the
degree of lightness or darkness of the various parts
of the image. (2) A term applied to the color of the
image in a photographic print; that is, warm, cold,
sepia, and so forth.
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