写出光线：描述它的作用，而不是设备

Unretouched photograph of a 35-year-old man reading a letter at a kitchen table, an ordinary face, a grey sweater, medium shot at eye level. [one sentence] Natural colour, low saturation.

Unretouched photograph of a 35-year-old man reading a letter at a kitchen table, an ordinary face, a grey sweater, medium shot at eye level. Lit with a book light. Natural colour, low saturation.

Unretouched photograph of a 35-year-old man reading a letter at a kitchen table, an ordinary face, a grey sweater, medium shot at eye level. A very soft, wrapping light comes from camera left; the source is out of frame. It falls across his face and the letter and leaves only a faint, soft-edged shadow on the right side of his face. Natural colour, low saturation.

Unretouched studio portrait photograph of a 38-year-old carpenter, not a model: an ordinary face with fine lines at the eyes, uneven skin with visible pores, short dark hair with some grey, a little stubble, a faded charcoal work shirt, no jewelry, no makeup. He sits on a wooden stool against a mid-grey seamless backdrop, half-length from the waist up, looking just past the lens. LOOK: mid-grey backdrop #7D7F82 about 55%, charcoal shirt #3A3B3D about 25%, skin about 20%; low saturation, soft contrast, true blacks. CAMERA: a full-frame camera with an 85 mm lens at f/4 from 1.8 m, eye level, vertical frame. LIGHT: one 1.5 m octabox at 5500 K camera left at 45 degrees, a little above eye level, two stops over the shadow side; no other light. FORBIDDEN: teal, coloured light, smoothed or plastic skin, glossy highlights on the face, readable text or logos.

Unretouched studio portrait photograph of a 38-year-old carpenter, not a model: an ordinary face with fine lines at the eyes, uneven skin with visible pores, short dark hair with some grey, a little stubble, a faded charcoal work shirt, no jewelry, no makeup. He sits on a wooden stool against a mid-grey seamless backdrop, half-length from the waist up, looking just past the lens. LOOK: mid-grey backdrop #7D7F82 about 55%, charcoal shirt #3A3B3D about 25%, skin about 20%; low saturation, soft contrast, true blacks. CAMERA: a full-frame camera with an 85 mm lens at f/4 from 1.8 m, eye level, vertical frame. LIGHT: one large, soft key at 5500 K from out of frame, camera left at 45 degrees and a little above eye level; it wraps softly round the near side of his face and leaves a soft-edged shadow on the far cheek and a soft shadow on the backdrop behind him to camera right; the lit side two stops over the shadow side; the source is out of frame; no other light. FORBIDDEN: teal, coloured light, smoothed or plastic skin, glossy highlights on the face, readable text or logos.

Unretouched photograph from a documentary interview series about people who keep old ferries running. A 52-year-old ferry mechanic, not a model: a broad weathered face, deep lines at the eyes and forehead, uneven sun-darkened skin with visible pores, grey stubble, short grey hair, a little oil on his fingers. He wears a faded navy work jacket over a grey T-shirt, no jewelry, no watch. He sits on a steel stool in his workshop, his head turned a few degrees toward camera right, mid-answer; an ordinary moment, not posed. Behind him, 3 m back: a workbench with tools and a vice, two bench lamps, a limewashed wall. LOOK: weathered walnut #5A3E2B about 35%, warm limewashed wall #CBB89A about 30%, charcoal shadow #2A2724 about 25%, faded navy #2F3B52 about 10%; low saturation, soft contrast, true blacks; skin stays skin coloured. CAMERA: a full-frame documentary camera, a 58 mm lens at T2, medium close-up from mid-chest at seated eye level from 1.6 m, locked off; a little sensor noise in the shadows. LIGHT: a soft key at 5600 K from camera right at 45 degrees, a little above eye level, on the short side of his face (the side turned away from the camera), so the cheek nearer the camera falls into soft shade; the key is 1.5 stops over the shadow side; a black 4x4 solid camera left as negative fill; the two bench lamps in the background at 2700 K, two stops under his face. Every light is off frame: no light stands, softboxes, cables or fixtures visible anywhere in the picture. FORBIDDEN: teal, cyan or green spill, coloured light on the walls, teal and orange, RGB accent lights, smoothed or plastic skin, readable text or logos.

Unretouched photograph from a documentary interview series about people who keep old ferries running. A 52-year-old ferry mechanic, not a model: a broad weathered face, deep lines at the eyes and forehead, uneven sun-darkened skin with visible pores, grey stubble, short grey hair, a little oil on his fingers. He wears a faded navy work jacket over a grey T-shirt, no jewelry, no watch. He sits on a steel stool in his workshop, his head turned a few degrees toward camera right, mid-answer; an ordinary moment, not posed. Behind him, 3 m back: a workbench with tools and a vice, two bench lamps, a limewashed wall. LOOK: weathered walnut #5A3E2B about 35%, warm limewashed wall #CBB89A about 30%, charcoal shadow #2A2724 about 25%, faded navy #2F3B52 about 10%; low saturation, soft contrast, true blacks; skin stays skin coloured. CAMERA: a full-frame documentary camera, a 58 mm lens at T2, medium close-up from mid-chest at seated eye level from 1.6 m, locked off; a little sensor noise in the shadows. LIGHT: a soft key at 5600 K from out of frame, camera right at 45 degrees, a little above eye level, on the short side of his face (the side turned away from the camera), so the cheek nearer the camera falls into soft shade; the key is 1.5 stops over the shadow side; the camera-left side of the room is dark and nothing bounces light back, so the shadow side of his face stays deep; the two bench lamps in the background at 2700 K, two stops under his face. FORBIDDEN: teal, cyan or green spill, coloured light on the walls, teal and orange, RGB accent lights, smoothed or plastic skin, readable text or logos.

Unretouched photograph of a 35-year-old man reading a letter at a kitchen table, an ordinary face, a grey sweater, medium shot at eye level. Lit by a China ball. Natural colour, low saturation.

Unretouched photograph of a 35-year-old man reading a letter at a kitchen table, an ordinary face, a grey sweater, medium shot at eye level. Soft, warm light at about 2700 K comes from in front of him and a little to camera left, from just above his head height; the source is out of frame. It wraps round his face, his shoulders and the letter with gentle, soft-edged shadows. No lamps or bulbs anywhere in the picture. Natural colour, low saturation.

Unretouched photograph of a 35-year-old man reading a letter at a kitchen table, an ordinary face, a grey sweater, medium shot at eye level. [light line] Natural colour, low saturation.

[Where the light comes from: camera left, camera right, behind, or above the camera], [how big and soft it is: a large soft light, a small hard light], at about [color temperature: 2700 K for a warm household bulb, 5600 K for daylight] or [a time of day]. It [falls on what] and leaves [where the shadow goes]. The source is out of frame.