Sabattier effect:- part positive part negative effect formed when an emulsion is briefly re-exposed to white light during development, and then allowed to continue development. Also known as pseudo-solarization.
Safelight:- darkroom light of a color and intensity that will not affect light sensitized photographic materials.
Safety film:- term used to describe a film with a base that is not readily inflammable.
Sal-ammoniac:- ammonium chloride. used in some high speed developers.
Sandwiching:- combination of two or more negatives or film positives in the negative carrier or masking frame when printing or enlarging.
Saturated color:- pure color hue, undiluted by other colors, white or gray, i.e. the primary colors, red, yellow and blue are saturated colors.
Scale:- linear relation between the size of the subject and the size of its image.
Scanning electron microscope:- device used in photomicrography.
Schumann plate:- plate coated with an emulsion with so little gelatin content that the silver halide grains protrude above its surface. Used for photography in the ultraviolet region.
Screening:- conversion of a continuous tone image to a half-tone image.
Screen plate:- plate used in early additive forms of color photography.
Scrim:- lighting attachment which, when placed in front of a lamp, reduces its strength, usually by one stop, without affecting lighting quality or color.
Selective focusing:- method of adjusting the lens aperture and shutter speed to give a depth of field that will limit image sharpness to a particular area of the image.
Selenium:- light-sensitive substance which, when used in a barrier-layer construction, generates electrical current when exposed to light. Used in exposure meters.
Selenium cell:- light sensitive cell used in many types of exposure meters. It generates electricity in direct proportion to the amount of light falling upon its surface.
Self-timer:- mechanism for delaying the opening of the shutter for a given number of seconds after the release has been operated.
Self toning paper:- obsolete silver chloride paper used for contact printing in daylight.
Sensitive material:- in photography, refers to materials that react to the actinic power of light.
Sensitivity:- degree of response of a photographic emulsion to exposure to light.
Sensitometry:- scientific study of the response of photographic materials to exposure and development. It establishes emulsion speeds and recommended development and processing times.
Separation images:- technique of producing an image by combining photographs produced on a material or using equipment which is sensitive to one region of the visible spectrum.
Separation negatives:- black & white negatives, usually prepared in lots of three or four, which have been taken through filters which analyze the color composition of an original in terms of blue, green and red. They are used particularly in photomechanical color printing and dye transfer printing processes.
Shading:- see Local control.
Shadow detail:- details visible in areas that are darkest in the subject.
Shadows:- darkest areas in a photographic print.
Sheet film:- alternative term for cut film.
Shelf life:- length of time unused material or chemicals will remain fresh.
Shellac:- natural resin with a low melting point. It is mainly used on dry mounting tissue.
Shutter:- mechanical system used to control the time that light is allowed to act on the sensitive emulsion.
Shutter priority camera:- semi-automatic camera on which the photographer selects the shutter speed, and the camera automatically sets an appropriate aperture.
Shutter speed:- action of the shutter that controls the duration of an exposure. The faster the speed the shorter the exposure. Shutter speed settings are given in the fraction of a second. Each setting is half the duration of the preceding one in a constant scale, marked on the shutter speed dial or ring.
Side lighting:- light striking the subject from the side relative to the position of the camera. It produces shadows and highlights to create modeling on the subject.
Silhouette:- photographic image in which the subject is seen as a solid black shape against a light background.
Silicon release paper:- thin, heat resistant interleaving paper, used between a photographic print and textured material in a heated press. It allows remolding of the print surface yet prevents the two materials from sticking together.
Silk print:- image made on silk by means of the diazo or dye printing methods.
Silkscreen:- method of applying inks to paper or similar materials using a nylon stencil produced by photographic means.
Silver dye bleach material:- integral tripack printing material.
Silver halides:- light sensitive crystals used in photographic emulsions, i.e. silver bromide, silver chloride and silver iodide. The change from white to black metallic silver when exposed to light.
Silver nitrate:- chemical combination of silver and nitric acid. It is used in intensifiers, physical developers and photographic emulsions manufacture.
Silver reclamation:- system for recovering silver from exhausted solutions.
Silver recovery:- system of reclaiming silver from exhausted solutions.
Silver salts:- compounds of silver.
Simultaneous contrast:- effect that adjacent color hues have upon each other.
Single lens reflex (SLR):- stands for single lens reflex. It is a camera of 35mm or medium format in which a system of mirrors shows the user the image precisely as the lens renders it.
Single servo AF:- when focus is locked as long as the shutter release button is lightly pressed.
Sizing:- very dilute, gluey substance used to prepare surfaces for coating by filling in pores and giving even absorbance.
Sky filter:- outdated term for a filter which has a graduated density across its surface.
Sky shade:- alternative term for a lens hood.
Slave unit:- mechanism which fires other flash sources simultaneously when a photo-electric cell is activated by the illumination emitted by a camera linked flash.
Slide:- alternative term for a projection transparency.
Slit shutter:- narrow vertical slit either just in front of the emulsion or at a similar distance in front of the lens. Film is wound through the camera at a constant speed giving one long image along the length of the film.
Slow film:- film having an emulsion with low sensitivity to light. Typically films having an ISO or 50 or less.
Slow lens:- lens with a small maximum aperture, such as f/8.
Slow sync:- flash technique for using the flash at a slow shutter speed. Flash shooting in dim light or at night at a fast shutter speed often results in a flash-illuminated subject against a dark background. Using a slower shutter speed with the flash brings out the background details in the picture.
Slide:- photographic transparency mounted for projection. It represents first generation production of an image.
Snapshot:- term once used to describe a photograph taken with the I (instantaneous) setting on cameras. The term originally came from rifle shooting, when little or no time is allowed for aiming.
Snoot:- cone shaped shield used on spotlights to direct a cone of light over a small area.
Sodium bichromate:- chemical used in intensifiers, toners and bleaches.
Sodium bisulfite:- chemical used in fixing baths as an acidifying agent.
Sodium carbonate:- alkaline accelerator used in many general purpose and print developers.
Sodium chloride:- used in some bleaches and reducers.
Sodium hexametaphosphate:- water softener.
Sodium hydrosulfite:- used as a fogging agent in reversal processing.
Sodium hydroxide:- highly active alkaline accelerator used in conjunction with hydroquinone to produce high contrast developers.
Sodium metabisulfite:- used as an acidifying agent in acid fixing baths.
Sodium sulfide:- chemical used in sulfide (sepia) toning.
Sodium sulfite:- chemical commonly used as a preservative in many developing solutions.
Sodium thiocyanate:- alternative to potassium thiocyanate and is used as a silver solvent in physical and ultra-fine grain formulae.
Sodium thiosulfate:- chemical used in many fixing solutions. It converts unused halides to a soluble complex which can be removed by washing.
Soft developer:- paper developer that can be used alone or in combination with other developers (two-bath development) to achieve more subtle contrast control.
Soft focus:- definition of a diffused image. This can be achieved at the camera or enlarging stage.
Soft focus lens:- lens, uncorrected for spherical aberrations, used to produce a soft focus effect.
Solarization:- reversal or partial reversal of tones in a photographic image caused by vast amounts of over-exposure. It is often inaccurately used to describe the partial reversal effect caused by fogging photographic material with light, which is actually the Sabattier effect.
Solubility:- in general terms is the ease with which a solid will mix homogeneously with water to provide a chemical solution.
Spacing bracket:- device used to position the camera at the right distance from the subject for the lens focus setting in closeup work.
Spectral sensitivity:- relative response of a photographic emulsion to each of the colors of the spectrum, including infrared and ultraviolet.
Spectrum:- usually used in reference to the visible part of the electro-magnetic spectrum, i.e. the color bands produced by diffraction, and arranged according to wavelength, when white light is passed through a prism.
Speed:- sensitivity of a photographic emulsion to light. Films are given ISO or DIN numbers denoting speed characteristics.
Spherical aberration:- lens fault which causes loss of image definition at the image plane. Its affects are reduced by stopping down.
Split image rangefinder:- see Rangefinder.
Spool:- bobbin like object consisting of a narrow core with flat disks on either end, around which the film is wound.
Spotlight:- artificial light source using a fresnel lens, reflector, and simple focusing system to produce a strong beam of light of controllable width.
Spot meter:- used to get accurate light readings of a small part of a subject. It uses a narrow angle of view to measure within limited areas.
Spotting:- method of retouching. Blemishes or unwanted details are removed from negatives and prints by brush and dye or pencil.
Spotting:- Retouching a processed print with a pencil or brush (with watercolors or dyes) to eliminate spots left by dust or scratches on the negative.
Stain:-Discolored areas on film or paper, usually caused by contaminated developing solutions or by insufficient fixing, washing, or agitation.
Stop Bath:- An acid rinse, usually a weak solution of acetic acid, used as a second step when developing black-and-white film or paper. It stops development and makes the hypo (fixing bath) last longer.
Stopping Down:- Changing the lens aperture to a smaller opening; for example, from f/8 to f/11.
Sprocket holes:- perforations on both edges of 35mm film, which engage with the teeth of the film transport mechanism.
Squeegee:- tool with rubber blades or rollers, used to squeeze water out of wet prints.
Stabilization:- alternative method of fixing. Unused halides are converted to near stable compounds, insensitive to light. No washing is required.
Stabilizer:- final solution often used in color processing which leaves the dyes produced by chemical development more stable and fade resistant.
Staining developer:- developer, such as pyro, in which the oxidation products give extra image density by staining the gelatin.
Stand:- alternative name for a tripod.
Standard lens:- lens with a focal length approximately equal to the diagonal of the film format with which it is used.
Stand camera:- large format camera usually mounted on a rigid stand.
Static marks:- jagged fog marks on negatives as a result of a very dry film being rewound or unwound too rapidly.
Step wedge:- printed series of density increases, in regular steps from transparent to opaque. Its a method of making exposure tests when enlarging.
Stereoscope:- viewer which accepts pairs of stereoscopic images.
Stereoscopic camera:- camera designed to take simultaneous images of the same subject from viewpoints separated by the same distance as that between the eyes.
Stereoscopy:- method of creating a three dimensional effect on a two dimensional surface using a pair of images taken from slightly different viewpoints, and viewed through specially made stereo viewers.
Still life:- inanimate subject, either in the studio, or outdoors, normally arranged to make full use of form, shape and lighting.
Stock solution:- processing chemicals which may be stored in a concentrated state and diluted just before use.
Stop:- aperture of a camera or enlarging lens.
Stop bath:- chemical bath whose purpose is to stop development by neutralizing unwanted developer. This increases precision of development and prevents carry over of one chemical into another during development.
Stopping down:- reducing the size of the lens aperture and thus the amount of light passing into the camera. It increases depth of field.
Stop down metering:- TTL metering in which the light is measured at the picture-taking aperture.
Straight photography:- term used to describe picture making with minimal manipulation of the photographic process.
Stress marks:- black lines on a photographic emulsion caused by friction or pressure.
Strobe light:- low power electronic flash that can fire repeatedly at regular, controlled intervals.
Studio camera:- term given to a large format 12 x 15 inch camera on a wheeled stand.
Subbing:- layer applied to a photographic support as a foundation for the emulsion.
Subject:- person or thing photographed.
Subjective photography:- interpretive image of the subject, with results influenced by the attitude of the photographer.
Sub-miniature camera:- camera using a film format smaller than 35mm.
Substantive film:- color film in which the color couplers are contained within the emulsion.
Subtractive primaries:- yellow, magenta and cyan.
Subtractive synthesis:- combination color system used in modern photography materials. The complimentary colors of yellow, magenta and cyan are formed to provide a reasonably full color image.
Successive color contrast:- trick of the human eye by which the impression of a color is influenced by an immediately preceding color stimulus.
Sulfide toning:- conversion of a black metallic silver image into a brown dye image. Usually known as sepia toning.
Sulfuric acid:- high corrosive chemical used in reducers.
Supper coat:- top coating of non-sensitized gelatin added to sensitized emulsions to form a protective layer.
Supplementary lenses:- additional lens elements used with the standard camera lens to provide a new focal length.
Surface development:- development process in which the image forms primarily on the surface of the emulsion and then penetrates deeper.
Surge marks:- streaks on the image from each of the sprockets holes of 35mm film caused by excessive agitation.
Surrealism:- originally an early 1920s artistic movement, now taken to indicate the production of unreal images which defy reason.
Swing back/front:- term used to describe the movable lens and back panels of most view and monorail cameras. They allow manipulation of perspective and depth of field.
Symmetry:- effect of an evenly balanced arrangement of visual information, such as pattern, on either side of a central division.
Synchronized flash:- method of synchronizing flash light duration with the maximum shutter opening.
Synchro-sunlight:- system of combining daylight and flash to achieve a controlled lighting ratio.