A rim light is a light placed behind the subject and off to one side, aimed back toward the camera, so that it lights only a thin bright line along the subject’s edge. That line pulls a dark subject off a dark background, shows the shape of a head, shoulder or bottle that would otherwise vanish, and gives a flat picture depth.
The idea is simple; getting it right is all placement. A few degrees of movement change a rim from a fat slab of side light to a hairline, or from a clean edge to a lens full of flare. This page explains why only the edge lights up, gives the angles in numbers, shows how to set the rim’s brightness against your main light, and ends with a ten minute exercise using an orange, a tennis ball and a desk lamp.
Rim light, kicker, hair light and backlight: what each name means
Lighting people use these words loosely, and the same lamp can get three names on three sets. The useful distinction is where the light sits and what it touches:
- Rim light: Where the light sits: Behind the subject and to one side, roughly 120 to 160 degrees from the camera. What it lights: A line along one edge: cheek, jaw, shoulder, arm, the side of a bottle.
- Kicker: Where the light sits: Behind and to the side, usually lower and closer to the subject’s side than a rim. What it lights: A sliver of the cheek and side of the face on the shadow side.
- Hair light: Where the light sits: Above and behind the head. What it lights: The top and back of the hair and the tops of the shoulders.
- Backlight: Where the light sits: Anywhere behind the subject, aimed toward the camera. What it lights: A position, not a look: it can give a rim, a glow through thin material, or a silhouette.
In a classic three-point lighting setup the third light is often called the back light, and it does the job of a hair light or a rim light depending on where it is placed. The hair light, and the background light that often works beside it, have their own page: hair light and background light.
Why only the edge lights up
Picture a round head lit from behind and to the right. The surfaces facing the light are on the back of the head, which the camera cannot see. The surfaces facing the camera are on the front, which the light cannot reach. The only surfaces that face both at once are a narrow band near the outline, where the head curves away from the lens. That band is the rim.
Three things make that band brighter than you might expect:
- Grazing reflection. Skin, hair, glass, polished wood and anything with a slight sheen reflect far more light when the light arrives at a low, skimming angle and leaves toward the viewer at a low angle. The edge of a forehead or a bald head can go from dull to glaring with a small move of the light.
- Forward scatter. Fine hair, fur, feathers, wool and fuzz send much of the light that hits them onward in roughly the direction it was already traveling. Lit from behind, each strand glows, so a fuzzy outline lights up far more than a smooth one.
- Thin, translucent edges. Ears, the edges of leaves and petals, and loose fabric let light through, so they glow when the light is behind them.
There is one more condition, and it is the one most often missed: a rim only shows against something darker than itself. A bright edge against a bright sky or a white wall disappears into it. Rim light and a dark background work as a pair.
How the angle sets the width of the rim
For a smooth, round subject you can work out how much of it the camera sees lit. With the light at angle θ from the camera (0 degrees is beside the lens, 180 degrees is directly behind the subject), the lit band at the widest point of the subject is a fraction (1 + cos θ) ÷ 2 of the subject’s full width. The diagram at the top of the page draws four of these; the table gives more:
| Light angle from the camera | Lit part of the subject’s width | What it looks like |
|---|---|---|
| 90 degrees | 50% | Side light: half lit, half dark |
| 110 degrees | 33% | A broad edge that wraps onto the cheek |
| 120 degrees | 25% | A thick rim |
| 135 degrees | 15% | The classic rim |
| 150 degrees | 7% | A thin line |
| 160 degrees | 3% | A hairline |
| 170 degrees | under 1% | Almost nothing on smooth surfaces; hair and fur still glow |
A real head is not a ball, hair sticks out past the skin, and a large light source softens the boundary, so treat the percentages as a guide to direction, not a prediction. What they show is how quickly the rim shrinks: the 30 degrees from 120 to 150 cut it to about a quarter of its width. That is why rim lights are adjusted in small moves.
Where to put a rim light
The angle
Start with the light about 135 degrees from the camera: behind the subject and well off to one side. Then move it along an arc around the subject while you watch the edge. Bring it forward, toward 110 to 120 degrees, and the rim widens and starts to wrap onto the cheek and the front of the shoulder. Take it back, toward 150 to 160 degrees, and the line thins until it only catches hair. If the subject turns their head, the angle changes for the face even though the light has not moved, so set the pose first.
The rim usually goes on the side opposite the key light, so it outlines the shadow side of the face, where the dark background and dark cheek would otherwise merge. A rim on the same side as the key is not wrong, but it lands on an edge that is already lit and does less work.
The height
For a portrait, put the light a little above head height and tilt it down toward the shoulder and side of the head. Too low and it lights the neck and jaw from below, and it is far more likely to shine straight into the lens. Too high and it catches only the top of the hair and makes hot spots on the forehead, ears and tip of the nose while missing the shoulder. For a product, a bottle or a car, set the height to match the edge you want to draw.
The distance and the size of the source
Moving the light closer makes the rim brighter, by the inverse square law: half the distance gives four times the light, two stops more. It also makes the source larger relative to the subject, which spreads the rim into a wider band with a softer inner edge. Moving it away gives a narrower, crisper, dimmer line. Close in, a small move forward or back changes brightness a lot, so lock the stand before fine tuning the power.
One rim or two
Two rims, one each side behind the subject, outline both edges. This is common for athletes, cars, bottles and dramatic low-key portraits where the front is barely lit. Set them one at a time, and expect them to need different power, because the subject is rarely symmetrical and the key light already brightens one side.
Sketching a setup before you build it saves time on set. The lighting diagram tool lets you place the key, the rim, flags and the camera on a plan like the one above and save it for next time.
Want the rim to sit on a background that is dark enough to show it? How to separate your subject from the background covers distance, light and tone behind the subject.
Choosing the light source for a rim
Any light can make a rim. What matters more than the kind of light is how well you can stop it going where you do not want it: onto the background, onto the front of the face, and into the lens.
- Strip softbox with a grid. The most common studio rim source. A tall, narrow box puts an even line down the whole height of a standing person or a bottle, and the grid keeps the light off a nearby backdrop. See softbox for the sizes and shapes and grid for how a grid narrows the beam.
- Standard reflector and grid. A bare head in a small metal reflector, gridded, gives a crisp, bright rim with little spill. Good for a hard, graphic edge.
- Snoot. A tube that throws a small circle of light. Useful for a rim on one part of the subject, such as the hair on one side, but too narrow to cover a full figure.
- A small flash. A speedlight with a grid or a strip of card taped around the head is a cheap rim light, indoors or out at night. Set it in manual power so its output does not change from frame to frame.
- Continuous light. An LED panel or lamp lets you see the rim before you shoot, which makes learning placement much faster.
- The sun, a window or a street lamp. Free and often the best rim of all; see the natural light section below.
A common rule says rims need hard light. It is half true. A small or distant source draws a crisp line, a large close source draws a wider, softer one, and both are useful. What spoils a rim is not softness but spill: a big ungridded softbox lights the background, the side of the face and the lens as well as the edge. The difference between the two kinds of light is set out in hard vs soft light.
Setting the rim’s brightness against the key
Build the light in order. Set up the key light and get the face right first. Then turn the key off and switch on only the rim, so you can see exactly what it touches: if it lights anything except the edge, move or flag it now. Then turn both on together and adjust the rim’s power.
For a starting point, set the rim to the same output as the key at a similar distance, take a frame, and adjust in steps of a third of a stop. Expect to end anywhere from about a stop below the key to a stop or more above it. The final setting depends on three things:
- The surface. Blond, gray and white hair, shiny skin and glossy products reflect a grazing light strongly and need less. Dark, dense hair and matte fabric soak it up and need more.
- The background. The darker the background, the less power a rim needs to stand out. Against a mid-tone gray it needs more.
- The look. A rim that just separates the subject should be noticed only when it is missing. A rim that is the style of the picture, as in sports and music portraits, can be the brightest thing in the frame.
Do not trust a meter reading of the rim light to tell you how bright the edge will look. A handheld meter held at the subject’s cheek and pointed at the rim light measures how much light arrives, but at a grazing angle how much reaches the lens depends on the surface: shiny skin may throw back far more than the number suggests, matte cloth far less. Judge on the picture itself. Turn on the highlight warning and zoom in on the edge. A rim that blinks over a whole cheek has lost its texture and needs a third to two thirds of a stop less. A rim that blinks only on a few hair strands is usually fine.
How do photographers describe the balance between two lights in numbers? Lighting ratio explains stops, ratios and how to measure the key against the fill.
Exposing a rim-lit picture
With studio lights, set the exposure for the key light on the face, exactly as you would without a rim. The rim’s brightness is then controlled by its own power, not by the camera.
With natural light, or any time the rim is the main light, the camera’s meter needs help. Evaluative or matrix metering sees a mostly dark frame and brightens it, which burns out the rim and lifts the dark background to gray. Two ways round it:
- Dial it down. In aperture or shutter priority, set exposure compensation to about −1 and check the rim. Against a very dark background −1.7 or −2 is common. Stop when the rim holds its color and texture.
- Meter the bright edge and lock it. Use spot metering on the lit rim or a bright part near it, hold that reading with AE lock, then recompose. Because a spot meter makes whatever it reads a mid-tone, add back about +1 to +1.7 so the rim sits brighter than mid-gray, then check the highlight warning.
Practise the first fix in the camera simulator: on a dark stage, evaluative metering brightens the frame and washes out the lit performers, so dial in exposure compensation until they hold their detail.
If you also want detail on the face, add light to the front with a white reflector or fill light and expose for the face, checking that the rim has not clipped.
Keeping flare out of the lens
A rim light points roughly at the camera, so it is always close to shining into the lens. When it does, you get lens flare: colored blobs, and a gray haze over the whole picture that is easy to miss on the back of the camera and obvious on a large screen.
The test is simple. With a studio or lamp light, put your eye near the lens and look toward the light. If you can see the front of the light or its modifier, so can the lens. (Never do this with the sun; for the sun, look at the frame for haze instead.) Then fix it with one of these, in rough order of convenience:
- Move the light back a little or raise it until it drops out of the lens’s view.
- Put a flag, a sheet of black card or foam board, on a stand between the light and the camera, just outside the frame.
- Use a lens hood, or shade the front of the lens with your hand or a card held out of shot.
- Hide the light directly behind the subject, which only works when the rim is at 160 to 180 degrees.
A grid or snoot narrows the beam and keeps it off the background, but it does not stop flare on its own: if the face of the grid can see the lens, the lens still gets a direct hit.
Rim light with the sun, a window or a street lamp
You do not need studio lights for a rim. Put the subject between you and a low sun, step to one side until the sun sits just off the edge of their head or shoulder, and choose a viewpoint where the background behind them is in shade: trees, a building in shadow, a dark hillside. The hour after sunrise and before sunset works best, because a low sun sits behind a standing person instead of on top of their head, and it is soft enough to manage; see golden hour photography. Fill the face with a reflector or a pale wall, or let it fall dark for drama.
Fur, feathers, seed heads and long grass are the easiest natural subjects because forward scatter makes every strand glow. Animals in early light against a shaded wood are the classic case in wildlife photography. Smoke, mist and dust also scatter light forward, so a rim-lit subject in haze often sits inside a visible glow; see fog photography.
At night, a street lamp, a shop window or car headlights behind a person do the same job. Indoors, a window behind and to one side of a subject sitting in a dim room gives a soft rim with no equipment at all.
Never look at the sun through an optical viewfinder or point a long lens at it, and do not leave a camera pointed at the sun on a tripod; it can damage your eyes and the camera.
Wondering what else light from behind can do, from silhouettes to glowing leaves? Backlighting: silhouettes, rim light and dramatic effects covers the whole family.
Adding color to the rim
Because a rim sits on the outline, a colored rim reads strongly even when it is small. Put a gel over the rim light and leave the key white, and the subject gets a colored edge against a neutral face. A warm, orange rim with a neutral or cool key suggests a sunset or a lamp somewhere behind the subject; a blue rim suggests moonlight, a screen or night sky. Two rims in two contrasting colors, one each side, are a common look in music and sports portraits.
A gel absorbs some light, and the stronger the color, the more it absorbs, so expect to raise the rim’s power after adding one. Set white balance for the key light, otherwise the camera will try to neutralize the colored rim.
Common mistakes with rim light
- The rim disappears into the background. The background is as bright as the rim. Darken it: move the subject further from it, flag or grid the rim so it does not hit it, or choose a darker backdrop.
- Gray, low-contrast picture. The rim light is shining into the lens. Run the eye-at-the-lens test and flag it, move it, or shade the lens.
- Spill on the cheek or nose. The light is too far forward or too large and unflagged. Move it back along the arc, or add a grid.
- Burnt-out white edge. Too much power for the surface. Reduce in third-stop steps until the highlight warning shows only on a few strands.
- Hot spots on the forehead, ears and nose tip with no shoulder rim. The light is too high. Lower it and tilt it toward the shoulder.
- A rim that works on one face and fails on the next. Hair color changed. Dark hair needs more power or a closer light than blond.
- Rim on the lit side. The rim and key are on the same side, so the edge that needed separating stays dark. Move the rim to the side opposite the key.
- Trusting the meter on the rim. A reading at the cheek does not tell you how a grazing light will look on skin or hair. Judge the picture and the highlight warning.
Try this: walk a lamp around an orange and a tennis ball
You need about ten minutes, a dark room, a desk lamp or a second phone’s flashlight, a dark cloth or sweater for a background, an orange and a tennis ball. Set the orange on a table in front of the dark cloth, and shoot from the front with a camera or phone at the same position every time.
- Put the lamp level with the orange at 90 degrees from the camera, to its right. Take a picture. On a phone, tap the orange and drag the brightness down until the lit side shows texture.
- Move the lamp along an arc behind the orange to about 120, 150 and finally 180 degrees from the camera, keeping the same distance. Take a picture at each. At 180 degrees the orange must hide the light completely; a phone flashlight is the easiest light to hide.
- Replace the orange with the tennis ball and repeat the 150 and 180 degree shots.
- At 150 degrees, look at the frame for haze. Then hold a book or a sheet of card between the lamp and the camera, just out of frame, and shoot again.
How to judge the result: in the four orange shots, the lit band should shrink from half the orange to a hairline, roughly matching the table above, and the 180 degree shot should be almost dark. The tennis ball at 180 degrees should still show a fuzzy halo, which is forward scatter at work, and it is why hair and fur rim so easily. Pick the frame where the edge is clean, nothing spills onto the front, and the background stays dark. If the card shot has deeper blacks than the one before it, the lamp was flaring into the lens.
Rim light questions
Is rim light the same as backlight?
No. Backlight names a position: any light behind the subject. Rim light is one result of that position, a bright line along the edge, which you get when the light is a little to one side and the background is dark. The same backlight with the exposure set for a bright background gives a silhouette instead.
How bright should a rim light be compared to the key?
There is no fixed ratio, because how bright the edge looks depends on the surface and the background as much as on the light. Start with the rim at the same output as the key, then adjust in third-stop steps until the edge is clear but not clipping. Most results land somewhere from a stop below the key to a stop or more above it.
Can I make rim light with only one light?
Yes. Put the single light behind and to the side, and use a reflector or a white wall in front to bounce some of it back onto the face, or let the front stay dark for a low-key look. Outdoors, the sun is the rim and a reflector is the fill.
Why does my rim light cause a hazy, washed-out picture?
The light can see the lens, so it is flaring. Move the light back or up until it drops out of the lens’s view, or put a flag between it and the camera, and use a lens hood.
Does rim light work on dark skin and dark hair?
Yes, and it is often most useful there, because dark hair on a dark background is exactly what merges without it. Dark hair and skin reflect less of a grazing light, so they usually need more rim power or a closer light than pale subjects.
Curious how the direction of any light, not only from behind, changes a subject? Direction of light compares front, side, top and back light.