In short: Work out frame width first: distance times sensor width, divided by focal length. On a Super 35 sensor, a 35mm lens at 5m covers about 3.6m. Measure the distance to the backdrop, not just the subject, and keep that width inside the cove. Put the lens near the subject's eye line and check the top of frame for the grid.
On a cove, three numbers fix your shot: the focal length, the distance from camera to subject, and the height of the lens. Our White Space cove is 5.3m by 7.1m with 4.5m to the grid, which is small enough that a wide frame can see past the white. The sums below let you choose lenses and a camera position before you arrive.
The sums
For a rectilinear lens, the width of picture you get at a given distance is:
width covered = distance × sensor width ÷ focal length
In a 16:9 frame the height is a little over half the width, about 0.56 times it. The tables use a Super 35 sensor about 25mm wide and a full-frame sensor 36mm wide. Your camera may differ by a millimetre or two, so check yours on the field of view and focal length calculator. The lens and sensor crop cheat sheet helps if you are moving between formats.
Width covered on a Super 35 sensor, in metres:
| Lens | At 3m | At 4m | At 5m |
|---|---|---|---|
| 24mm | 3.1 | 4.2 | 5.2 |
| 35mm | 2.1 | 2.9 | 3.6 |
| 50mm | 1.5 | 2.0 | 2.5 |
| 85mm | 0.9 | 1.2 | 1.5 |
Width covered on a full-frame sensor, in metres:
| Lens | At 3m | At 4m | At 5m |
|---|---|---|---|
| 24mm | 4.5 | 6.0 | 7.5 |
| 35mm | 3.1 | 4.1 | 5.1 |
| 50mm | 2.2 | 2.9 | 3.6 |
| 85mm | 1.3 | 1.7 | 2.1 |
These figures are rounded, and focusing very close changes them slightly.
Measure to the backdrop, not just the subject
The width that matters on a cove is the width at the wall behind your subject. That distance is camera to subject plus subject to backdrop.
Say the subject stands 2m in front of the wall and the camera is 4m from the subject, so the wall is 6m away. A 35mm lens on Super 35 covers about 4.3m at that distance, which sits inside a room 5.3m wide. The same lens on a full-frame camera covers about 6.2m, which is wider than the room, so you would see past the cove. Either shoot longer, move the subject closer to the wall, or crop.
If you set up along the 7.1m length, a camera 6m from the wall still has some room behind it. Confirm the layout on the recce or with us before you commit to a lens that depends on every centimetre.
Where to put the subject
Stand the subject well forward of the wall. A metre and a half to two metres is a good starting point. It stops their shadow landing on the backdrop, lets you light the background separately and lets it fall a little softer. Closer is workable when the room is tight, though you then manage spill and shadows more carefully. Lighting a cove to white, and to black covers that side.
Choosing the lens
- 24mm: a full-length two-shot in a short distance. Keep faces away from the edges of frame, where wide lenses stretch them.
- 35mm: the all-rounder for full-length and three-quarter shots when you have the space.
- 50mm: mid shots and waist-up, with the background a little softer.
- 85mm: portraits and close-ups. It needs the most distance, and that is where the room runs out first.
Use the depth of field calculator when the background has to fall away, or to hold two people sharp at once.
Height of the lens
- Portrait or close-up: lens near the subject's eye line.
- Full-length: lens around waist to chest height, tilted very little. A strong tilt down shows more floor and the join where floor curves into wall, and a strong tilt up shows more wall.
- Low shots: a low camera looking up can see the top of the cove and anything hung from the grid. Look at the monitor, not at the plan.
- High shots: the grid is 4.5m up. Any camera or kit hung overhead is a rigging job for a competent person, who must assess the actual set-up. This page is general guidance, not a rigging instruction.
Worked example: two people, full length, 16:9
Two people standing side by side, head to toe with a little headroom, need a frame about 2.2m tall. On a Super 35 sensor with a 24mm lens, the frame is 2.2m tall at about 3.8m from the subjects, and 4.0m wide.
Put the subjects 1m in front of the wall and the wall is 4.8m from the camera. At that distance the 24mm lens covers 5.0m, which is just inside the 5.3m width. That works, and it is tight, so check both sides of frame on the monitor before you roll. With the subjects 2m forward, the wall would be 5.8m away and the lens would cover about 6.0m, wider than the cove.
The trade-off is plain: more distance between subject and backdrop gives cleaner lighting and a softer background, and it widens the frame at the wall. Changing orientation changes the sums. Shooting vertical turns the same width into height: a 35mm lens on Super 35 at 4m covers about 2.9m tall and 1.6m wide, which is enough for two people full-length. The page on shooting vertical and horizontal in one day explains how to plan both orientations.
Common mistakes
- Choosing a lens from the subject distance alone. Work out the width at the wall.
- Pressing the subject against the backdrop. Shadows and spill follow.
- Checking the sums but not the monitor. The sums tell you where to start, and the monitor tells you what you got.
- Forgetting the camera sensor. A full-frame body and a Super 35 body show different pictures from the same lens.
- Putting faces near the edge of a wide frame. Wide lenses stretch faces and cars at the edges.
The White Space page has the room's full details, and what fits on the cove shows real examples of subjects and lenses.
Related guides
- Field of view and focal length calculator, by sensor
- Depth of field calculator, with a worked example
- Data rate and storage calculator for camera files
- Frame rates and shutter: the 180 degree rule and flicker-free shutters for UK 50Hz
- Lens and sensor crop cheat sheet
- All guides and tools
The picture at the top of this page is an illustration, not a photograph of a client or a real job.
Questions we get asked
What lens should I use on an infinity cove?
It depends on the shot and the room. A wide lens such as 24mm gets a full-length two-shot into a short distance, a 35mm or 50mm suits full-length and mid shots, and an 85mm suits portraits. Work out the frame width at the backdrop first so you stay inside the cove.
How far should the subject stand from the cove wall?
A metre and a half to two metres is a sensible starting point. It keeps shadows off the wall, gives you room to light the background separately and lets the background fall softer. Closer is possible when the room is tight, but expect to manage spill and shadows more carefully.
How high should the camera be on a cove shoot?
Set the lens close to the subject's eye line for portraits and around waist to chest height for full-length shots. Tilting down shows more floor, and tilting up shows more wall and eventually the top of the cove and the lights, so check the monitor rather than assuming.
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