レンズ、外観、構図に関する用語

An anamorphic lens uses cylindrical glass to squeeze a wider field of view onto the sensor along one axis, then the image is stretched back out in post to give a wide 2.39:1 frame. The squeeze is why the look comes with oval highlights, horizontal streak flares and stretched edge distortion.

anamorphic · anamorphic look · squeeze factor

Aspect ratio is the proportion of a frame's width to its height, written as width:height. It fixes the shape of the image before anything is placed inside it, which constrains composition more than any other single setting. 16:9 is the widescreen default, 9:16 is vertical, and 2.39:1 is the wide cinema shape.

16:9 aspect ratio · 9:16 aspect ratio · 2.39:1 aspect ratio · cinemascope · frame ratio

Bokeh is the aesthetic character of the out-of-focus areas in an image, not the amount of blur. It covers the shape of defocused highlights, how smoothly the blur falls off, and whether the background dissolves cleanly or breaks into busy edges. Lens design produces it; aperture size only decides how much of it you see.

bokeh balls · background blur · out-of-focus highlights

Chromatic aberration is a lens defect in which different wavelengths of light focus at slightly different points, leaving coloured fringes along high-contrast edges. Real lenses are designed to suppress it, and digital work often adds it back deliberately because a trace of it reads as photographic.

colour fringing · purple fringing · chroma aberration · ca

Color grading is the creative stage of shaping an image's colour and contrast after the footage is matched and balanced. It follows colour correction, which fixes exposure and white balance so shots agree with each other, and its purpose is tone rather than accuracy.

grading · colour grading · color grade · colourist work

Depth of field is the distance between the nearest and farthest points in a scene that look acceptably sharp. A narrow zone isolates a subject against blur, a wide zone keeps foreground and background legible at once, and four things move it: aperture, focal length, subject distance, and sensor size.

DOF · focus range · deep focus

Film grain is the visible texture produced by clumps of light-sensitive silver crystals in photographic emulsion. Faster stocks have larger crystals and coarser grain. Digital sensors have no grain at all, so the look is now added deliberately to soften digital cleanliness and to signal a period or a format.

grain · grain structure · film emulation

A frame within a frame is a composition where something in the scene, such as a doorway, window, mirror, archway or overhanging branches, encloses the subject and forms a second border inside the edges of the shot. It adds depth, directs attention, and can imply confinement or observation.

framing device · natural framing · foreground framing · doorway shot

Golden ratio composition places the subject using the proportion 1:1.618, either as a phi grid whose lines sit closer to the centre than a thirds grid, or as a spiral that the eye is meant to follow inward. It is a slightly tighter alternative to thirds, and the spiral is the part that has practical value.

golden ratio · phi grid · golden spiral · Fibonacci spiral · composition techniques photography

Halation is the soft reddish glow that bleeds outward from bright areas into their surroundings, originally caused by light passing through film emulsion, reflecting off the backing and scattering back. Digital sensors do not produce it, so on modern images it is added deliberately as a signal of film capture.

halo glow · red halation · bloom · light bleed

Leading lines are linear elements in a frame, such as a road, a railing, a shadow edge or a row of columns, that pull the viewer's eye along a path toward the subject. They work because the eye follows continuity automatically, so the line decides what gets looked at first and in what order.

converging lines · diagonal lines · lines in composition

A lens flare is stray light that scatters and reflects between the glass elements of a lens instead of forming part of the image, showing up as streaks, coloured ghost blobs, or a milky wash over the frame. It happens when a strong light source is in the shot or just outside it.

flare · anamorphic flare · veiling glare · ghosting

A long exposure holds the shutter open long enough that moving subjects record as trails or smooth blur while static ones stay sharp. It turns a duration into a single image, which is why water becomes silk, crowds disappear and headlights become continuous lines.

slow shutter · light trails · time exposure

A LUT, or lookup table, is a file that maps every input colour to an output colour, so applying one transforms an image the same way every time. It is a fixed transform rather than an adjustment, which is why a LUT is a starting point or a technical conversion and not a substitute for grading.

lookup table · 3d lut · cube file · look up table

Motion blur is the smearing that appears when a subject or the camera moves while the shutter is open, so a single frame records a range of positions rather than one instant. Its amount is set by shutter speed relative to frame rate, and it is what makes movement on screen read as continuous.

shutter blur · movement blur · 180 degree shutter rule

Negative space is the empty area around and between the subjects in a frame. It is not leftover room: the size and shape of the emptiness is what gives the subject scale, direction and emotional weight, which is why deliberately empty frames read as calm, lonely, or tense rather than unfinished.

empty space · white space · breathing room

The rule of thirds divides the frame into a 3x3 grid and places the subject or the horizon on one of the four intersections or on the lines themselves, rather than dead center. Offsetting the subject leaves unequal space around it, which gives the frame a direction and keeps the eye moving.

thirds grid · off-center composition

A shallow depth of field means only a thin slice of the scene is sharp while everything nearer and farther falls into blur. It is the standard way to isolate a subject from a background, produced by combining a wide aperture, a longer lens and a short distance to the subject.

shallow focus · subject isolation · blurred background look

Symmetrical composition places the subject on a central axis with the frame balanced on either side, so the arrangement reads as deliberate rather than observed. It is the opposite instinct to the rule of thirds, and it signals order, formality or control.

symmetry · centred composition · mirrored framing

Teal and orange is a grading convention that pushes shadows and background toward blue-green while keeping skin warm, so faces separate from their surroundings. It works because skin tones and teal sit opposite each other on the colour wheel, and it became the default blockbuster grade for exactly that reason.

orange and teal · complementary grade · blockbuster grade

A tilt shift lens can move independently of the sensor in two ways. Tilt swings the plane of focus so it no longer sits parallel to the sensor, and shift slides the lens sideways or up to keep vertical lines parallel. Tilt is what produces the famous miniature effect; shift is what fixes leaning buildings.

tilt shift lens · miniature effect · perspective control lens