Photography terms starting with S

Short Lighting Lighting & Flash A portrait approach in which the side of the face turned away from the camera is the lit side.

Shot Noise Sensors & Digital Capture e⁻ (electrons) The unavoidable randomness in the arrival of photons, which produces grain even from a perfect sensor. SNR = √N

Shutter Actuation Count Cameras, Formats & Systems count The running total of exposures a camera's mechanical shutter has made, recorded in the file metadata.

Shutter Angle Motion, Video & Creative Techniques degrees A way of expressing shutter speed relative to frame rate, inherited from the rotating disc shutters of film cameras. Shutter speed = 1 / (fps × 360/angle)

Shutter Priority Exposure & Metering A semi-automatic mode, marked S or Tv, in which the photographer sets shutter speed and ISO while the camera chooses aperture.

Shutter Speed Exposure & Metering seconds The length of time the shutter stays open, controlling both total exposure and how much subject or camera movement is recorded as blur. t = 1 / denominator

Sidecar File Files, Metadata & Workflow KB A small companion file stored next to a raw file, holding edits and metadata that cannot safely be written into the raw itself.

Signal-to-noise Ratio Sensors & Digital Capture dB or ratio The ratio between the useful signal recorded and the noise accompanying it, which determines apparent image cleanliness. SNR = signal / noise

Silhouette Motion, Video & Creative Techniques stops An image in which the subject is rendered as a dark shape against a much brighter background.

Silver Halide Film, Darkroom & Historic Processes The light-sensitive compounds — silver bromide, chloride and iodide — that form the active ingredient of photographic emulsions. AgBr, AgCl, AgI

Simplification Composition & Visual Design The reduction of a scene to its essential elements by choice of viewpoint, framing, focus and timing.

Single-lens Reflex (SLR) Cameras, Formats & Systems A camera design in which a hinged mirror reflects the taking lens's image up into the viewfinder, then swings clear when the shutter fires.

Single-point AF Focus & Depth of Field An area mode in which the camera uses one selected focus point and ignores everything else in the frame.

Single-servo Autofocus Focus & Depth of Field An autofocus mode, marked AF-S or One Shot, that focuses once and then locks while the shutter button is held halfway.

Sky Replacement Post-Processing & Retouching Substituting the sky in a photograph with one from another image, with automatic masking and colour matching.

Slow Motion Motion, Video & Creative Techniques × Footage recorded at a higher frame rate than its playback rate, so action appears to unfold more slowly. Slowdown = capture fps / playback fps

Slow Sync Flash Motion, Video & Creative Techniques seconds Combining flash with a shutter speed long enough for ambient light to register, so a sharp subject sits within a blurred environment.

Smart Collection Files, Metadata & Workflow A collection defined by a saved set of criteria, which updates automatically as matching images are added.

Smart Object Post-Processing & Retouching A container layer that preserves its source data, so transformations and filters applied to it remain editable.

Smart Preview Files, Metadata & Workflow px A small lossy proxy of a raw file that allows editing while the original is offline.

Smartphone Camera Cameras, Formats & Systems A camera module in a phone, where computational processing compensates for the physical limits of a very small sensor and lens.

Snapshot Aesthetic Genres, Movements & Theory A deliberate adoption of the informal look of amateur photography — casual framing, direct flash, apparent artlessness.

Snoot Lighting & Flash degrees (beam angle) A tube fitted to a light to restrict its beam to a narrow circle.

Soft Light Lighting & Flash Light from a source that is large relative to the subject, producing shadows with gradual, feathered edges.

Terms starting with S