How to Light a Cyclorama or Infinity Cove

Lighting a cyclorama is two jobs that people keep trying to do with one set of lights. Job one is the background. Job two is the subject. Keep them separate and the whole thing becomes straightforward. Mix them and you spend the morning chasing a shadow you cannot get rid of.

This is the order that works, and the specific problems that come up at each stage. It is about the photo and video kind of cyc - a painted wall curving into the floor, also called an infinity cove - rather than the theatre cyclorama at the back of a stage, which has fixtures of its own. If the term is new, start with what an infinity cove is.

Light the background before anyone is in the room

Get the wash right while the floor is empty. It is far quicker to walk the cove with a meter than to adjust around a subject who is standing still and getting cold.

Position your background lights to one side or both sides of the cove, aimed across the surface rather than straight at it. A light pointed head-on puts its hottest part in the middle of the frame and lets the edges fall away. Two lights raking in from opposite sides overlap in the middle and give a much flatter field for less power.

Then measure. Take a reading at the left edge, the centre, the right edge, near the top of the shooting area and at the point where the curve meets the floor. You want those readings within about a third of a stop of each other. If you have no meter, shoot a frame and pull it into your grading software or use the camera's histogram at each point - anything more rigorous than looking at it, because eyes adapt and lie.

The floor is where evenness dies

The curve of a cyc means the floor sees your lights at a much shallower angle than the wall does, so it almost always reads darker. Two fixes: add a low unit aimed along the floor toward the camera position, or raise the whole background rig higher and steeper so the falloff onto the floor is gentler. Which one works depends on the room, and specifically on your ceiling height - so ask for the ceiling height before you book.

Even wash or deliberate gradient

Pure even white is the default request, and it is the right answer for e-commerce, cutouts and anything that has to composite. But an even wash is also flat, and flat backgrounds make flat pictures. A gradient - brighter behind the subject's head, falling off toward the edges of the frame - gives depth and draws the eye without adding a single prop.

To build one, do the opposite of the even wash. Use fewer, harder sources, aimed at one area, and let the falloff do the work. A single unit behind and below the subject aimed up at the wall gives the classic pool of light with darkness at the corners. Flag the spill so it stays a gradient rather than creeping outward into a bad wash.

An even wash is a technical requirement. A gradient is a choice. Know which one the job needs before you start rigging.

How far should the subject be from the cove?

Further than feels natural. Distance is the tool, and every problem in this article gets smaller the further the subject stands from the wall.

• Cast shadows disappear, because the subject's key light no longer reaches the wall with any strength.
• Background spill stops flattening the subject from behind.
• You can expose background and subject independently, which is the whole point.
• Your depth of field can throw the background slightly soft, which hides small imperfections in the cove surface.

The reason is the inverse-square law. With the key two metres in front of a subject who stands one metre off the wall, the wall is three metres from the key and gets only about a stop less light than the face, so it still takes nearly half the key's light and the shadow the subject throws onto it is plain to see. Move the subject three metres off and the wall is five metres from the key - more than two and a half stops down - and the background lights wash out what is left of the shadow with ease.

Two to three metres between subject and wall is a common starting point for a single person, with more for full-length and for a white that has to be clean from edge to edge. Keep the subject on the flat floor rather than on the curve, and remember that the further forward they stand, the more floor ends up in the frame. A car or large product is the same problem at a bigger scale, with reflections on top - how to photograph a car in a studio covers it.

For a clean white, run the background one to two stops above your subject exposure. One stop gives you a bright, believable white with edge detail intact. Two is properly clean. Beyond that, light starts bouncing off the wall back into the lens, wrapping around your subject's edges, lifting your blacks and quietly eating the detail in hair and dark clothing. Some people love that bloom. Just make it deliberate. To check a clean white in camera, turn on the highlight warning: it should just start flashing across the background and nowhere on the subject.

For grey or black on a white cove

Turn the background lights off entirely and control what reaches the wall from your subject lights. Flag hard, keep the subject far off the wall, and use tighter modifiers - a grid on the key, barn doors, a snoot. In a room that blacks out, a white cove with no light on it reads as anything from mid-grey down to near-black, and it will do it without a paint change.

Colour washing and gels

A colour-washed cove is one of the highest-value tricks in a studio day, because changing the background colour takes seconds and gives you a visibly different set of images from the same setup. Scope's Studio B has a colour-washable cove specifically for that — both coves are on the photography studio hire page.

Light the cove or paint it?

Paint puts the colour in the surface. It survives spill - white light landing on a painted red wall just makes a brighter red - and deep, dark shades are far easier to hold in paint than in light. The costs are time and flexibility: paint needs drying time, it gives you one colour for the day, and many studios charge to take a cove back to white, so check the repaint policy before you commit.

Light gives you a colour in seconds and a different one seconds later, which is why a day with several looks almost always goes that way. The trade is discipline. Every stray bit of white light on the wall pulls the colour towards pastel, so the rules below matter far more than they would on a painted wall.

Getting clean colour

Two routes. Gels on conventional heads are cheap, well understood, and mean physically swapping a sheet each time you change colour. LED units with adjustable colour let you change from the desk, which is faster on a day with a lot of looks, at the cost of hire.

Either way, the rules are the same. Keep white light off the coloured wall or the colour desaturates into pastel. Expose the coloured wash lower than you would a white one, because saturated colour reads as pale the moment it is overexposed - if the shade you wanted is coming out washed out, the fix is almost always less light, not more. And check your subject's skin for contamination: a strong background colour bouncing off a nearby wall onto a face is difficult to correct later.

Colour on the subject, not just behind

Once the wall is coloured, a small gelled rim or hair light in a complementary colour separates the subject and stops them merging into the background. This is where the shot stops looking like a person standing in front of a coloured wall and starts looking like a lit image.

Killing hotspots and floor shadows

Hotspots come from three sources: a light aimed too directly at the wall, a light too close to it, or a specular patch on the cove surface itself. In that order, the fixes are: rake the angle, move the unit back, and diffuse. A cove that has been repainted many times can develop patches of different sheen, and those will glare under a hard raking light while looking fine under a soft one.

Floor shadows come almost entirely from key lights that are too low and too close. Raise the key, move the subject forward, and flag the bottom of the key so the spill does not run along the floor toward the wall. If a shadow still refuses to go, put a light on the floor behind the subject aimed at the wall - filling the shadow is easier than removing it.

Lighting a cyclorama for video

Everything above holds for video, with a few differences. The subject moves, so the wall has to be even across the whole path they walk and everything a camera move reveals, not just behind a mark - light the path, not the spot. And continuous light shows you exactly what the camera will get, so walk the cove while you adjust and watch the hotspot move instead of shooting test frames.

Judge the white on scopes rather than on the monitor. On a waveform an evenly lit wall is a flat, thin line across the trace, and because the trace reads left to right like the frame, a hotspot shows up as a hump and a dark edge as a slope exactly where they sit. False colour does the same job at a glance: an even wall comes up as a single colour. Match the colour temperature of every background unit too, because two slightly different LEDs read as a visible shift across a white wall. Before the first take, check the fixtures for flicker at your frame rate and shutter speed - camera settings for studio shooting has the detail.

The kit you actually need

This is deliberately generic, because the right units depend on the size of your cove and your budget, and studios differ. At Scope, lights are not included in either studio's room rate - they are charged separately, so please enquire about our lights and send us the plan so we can quote for it. We have not published an in-house kit list, so ask before assuming anything below is waiting in the room.

• Background lights - at minimum two, one from each side. Wide reflectors, strip boxes or dedicated cyc units all work; the aim is broad, even coverage.
• A key light with a decent modifier - the softbox or octa size sets the character of the light on your subject.
• Fill - a reflector, a bounce board, or a second softer source.
• Separation - a rim or hair light, gridded so it does not spill onto the wall.
• Grip: flags, C-stands, sandbags. Control of where light does not go matters as much as where it does.
• A light meter, or the discipline to check the histogram at multiple points across the cove.

A workable running order

Background wash first, metered and confirmed. Subject positioned well off the wall. Key light, then fill, then separation. Test frame with a stand-in. Only then bring in the talent. Doing it in that order routinely saves half an hour, and half an hour of studio time is not nothing - room rates are on the rates page if you want to put a number on it.