An ultra-wide lens is a lens shorter than about 24mm on a full-frame camera, most often 12 to 20mm, that still draws straight lines as straight. It takes in an angle of view of 85 to 115 degrees from side to side, so it shows more than you can comfortably take in without turning your head, and it makes whatever is close to it look enormous against a setting that shrinks away behind.
That second part matters more than the first. People buy an ultra-wide to fit more in, then find their pictures full of small, distant things and empty ground. Used well, it does the opposite: you stand very close to something, and the lens lets you keep the whole world behind it in the frame. Below: where the ultra-wide range starts on each camera, why every millimeter counts at this end, what the lens does to shapes near the edges, why these lenses are built the way they are, and where they earn their place.
Using a 24 to 35mm lens, or want the everyday handling of any wide lens, such as keeping buildings upright and people away from the corners? How to use a wide-angle lens covers the whole wide range. This page is about the extreme end.
Where wide ends and ultra-wide begins
Width is an angle, and the angle depends on both focal length and sensor size. The usual reference is full frame (36 by 24mm). On a smaller sensor, divide by the crop factor to find the lens that gives the same view: an ultra-wide is about 10 to 16mm on APS-C (1.5x) and about 7 to 12mm on Micro Four Thirds (2x). The “0.5x” camera on a phone is an ultra-wide too, roughly 13 to 16mm in full-frame terms.
| Full-frame focal length | Horizontal angle | Vertical angle | Diagonal angle | Same view on APS-C (1.5x) | Same view on Micro Four Thirds (2x) | Corner stretch |
|---|---|---|---|---|---|---|
| 24mm | 74° | 53° | 84° | 16mm | 12mm | 35% |
| 20mm | 84° | 62° | 94° | 13mm | 10mm | 47% |
| 18mm | 90° | 67° | 100° | 12mm | 9mm | 56% |
| 16mm | 97° | 74° | 107° | 11mm | 8mm | 68% |
| 14mm | 104° | 81° | 114° | 9mm | 7mm | 84% |
| 12mm | 113° | 90° | 122° | 8mm | 6mm | 106% |
| 10mm | 122° | 100° | 130° | 7mm | 5mm | 138% |
Lens specifications quote the diagonal angle, corner to corner, which is why a 14mm lens is sold as “114 degrees” while the view across the frame is 104. “Corner stretch” is how much longer than wide a round object is drawn in the extreme corner of the frame; more on that below. Every lens in the table is rectilinear. A fisheye lens of the same focal length sees wider still, because it lets straight lines curve.
Every millimeter counts at the short end
At 50mm, a change of 2mm is invisible. At 14mm it is obvious. What a lens takes in of a flat scene in front of it scales with one over the focal length, so the same 2mm is a much bigger share of a short lens. Stand with your back to one wall of a room and point the camera at the opposite wall 3 meters away. Across a full-frame landscape frame you get:
- 24mm: 4.5 meters of wall
- 20mm: 5.4 meters
- 16mm: 6.75 meters
- 14mm: 7.7 meters
- 12mm: 9 meters
Halving the focal length doubles the width and the height you take in, so a 12mm lens shows four times the area of wall that a 24mm lens shows from the same spot. That is why a zoom that runs from 16 to 35mm and one that runs from 12 to 24mm feel like different tools at their wide ends, and why ultra-wides are sold in such small steps.
More angle is not automatically better. A wider lens also makes everything in the distance smaller, and it puts more of the frame into the zone where shapes stretch. The field of view page explains how the angle is measured and why it changes with sensor size.
Near things huge, far things tiny: the ultra-wide look
An ultra-wide does not change perspective by itself. Perspective comes from where you stand: an object 1 meter away is drawn ten times taller than the same object 10 meters away, whatever lens you use. What the ultra-wide changes is what you can include. Its angle is so wide that you can stand right beside a rock, a doorway or a flower and still have the mountains, the room or the sky in the same frame. The huge difference in distance between the near thing and the far things becomes a huge difference in size, and that exaggerated depth is the ultra-wide look.
The working rule is to get closer than feels right. Most ultra-wides focus down to about 20 to 30 centimeters, and the best foregrounds are often half a meter to a meter from the front of the lens. At 14mm, a stone 30 centimeters tall and 50 centimeters away fills about a third of the frame height, while a peak 2,000 meters high and 20 kilometers away is a sliver along the horizon. Move the camera and the foreground changes size dramatically; the background barely changes at all.
You can see this in the tool below. Set the shortest focal length, then move closer and farther: what grows and shrinks is the near subject, not the hills behind it. Keep the person the same size while widening the lens and the background falls away.
Camera height decides how the near and far parts connect. A camera at knee height or lower makes the foreground loom and pushes everything else to a thin band. Chest height reveals the ground in between. With an ultra-wide, a few centimeters of height make a visible difference to the nearest objects, so try both before deciding.
Close enough, but not sure the thing in front is worth it? Foreground interest goes through what makes a good foreground and how big it should be, and foreground, midground and background shows how to tie the near and far layers together.
Straight lines have a price: stretched edges
To keep straight lines straight, a rectilinear lens has to place a point that sits at angle θ from the center of the view at a distance proportional to tan θ from the center of the frame. Tan θ grows slowly at first and then very fast: at 45 degrees it is 1, at 60 degrees about 1.7, at 75 degrees about 3.7, and at 90 degrees it is infinite. So the outer degrees of the view are spread over far more of the sensor than the inner ones, and anything near the edges is pulled outward, away from the center. A ball in the corner is drawn as an egg pointing at that corner. In the extreme corner, a shape is drawn longer than wide by a factor of one over the cosine of the corner angle, which gives the “corner stretch” column in the table: 47 percent at 20mm, 84 percent at 14mm and more than double at 12mm.
Three things follow. First, a rectilinear lens can never reach 180 degrees, because the edge of the view would land infinitely far from the center; the widest practical ones stop at about 120 to 130 degrees across, and beyond that only fisheyes go. Second, the stretch is part of the projection, not a lens fault, so a lens profile in your editor does not remove it; profiles correct barrel or wavy lens distortion and darker corners. Third, it is invisible on rocks, clouds and grass and very visible on faces, round plates, wheels and the moon. At these focal lengths, keep people and circles near the middle of the frame.
A separate effect also gets blamed on the lens: a nose that looks huge or feet that look enormous. That is distance, because the part nearest the camera is much closer than the rest, and it happens in the center of the frame too. Perspective distortion explains the geometry.
Can you tell barrel distortion, edge stretch and perspective apart when you see them? Try the lens distortion quiz.
Why ultra-wides bulge: the retrofocus design
A simple lens focused at infinity sits one focal length in front of the sensor. For a 14mm lens that is 14mm, which is impossible on a camera with a mirror: the lens mount sits about 44 to 47mm in front of the sensor to leave the mirror room to swing up, and the glass cannot reach far into that space. Lens designers solved this with the retrofocus layout, sometimes called an inverted telephoto. A large front group that spreads light out comes first, and a converging group behind it brings the light to focus, so the last piece of glass can sit far enough back to clear the mirror while the whole lens still behaves like a 14mm.
Cameras without a mirror have a much shorter gap, about 16 to 20mm, which has allowed some smaller ultra-wides, but most are still built this way, partly because sensors record light that arrives at a steep angle poorly. The design explains most of what is unusual about handling these lenses:
- The domed front element. On many lenses wider than about 16mm it bulges past the rim with a built-in hood and no filter thread. It catches spray, fingerprints and dust, and those marks show up as glowing spots when you shoot toward light. Clean it before every backlit shot.
- Filters. Without a thread you need a large clamp-on holder for square filters, or a small slot at the rear on some lenses. On lenses that do take screw-in filters, a thick or stacked ring can cut into the corners at the widest setting; use one slim filter at a time.
- Polarizers. The sky darkens most at 90 degrees from the sun, and an ultra-wide sees a hundred degrees of sky at once, so a polarizing filter leaves a dark band across one part of a blue sky. Use it for reflections on water and wet rock, not for open sky.
- Darker corners. Light reaches the corners at a steep angle, and wide open the corners of many ultra-wides are one to three stops darker than the center. Stopping down two stops helps, and a profile in your editor fixes most of the rest. See vignetting and lens corrections.
- Softer corners. Many ultra-wides are sharpest in the middle and softer at the edges wide open, and some focus the corners at a slightly different distance from the center. Check corners at magnification, and stop down to f/5.6 to f/8 for landscapes.
- Flare and sunstars. With 100 degrees of view, the sun is often in the frame or just beside it, and the short hood shades little. Hide part of the sun behind something solid, and at small apertures the sun turns into a star, as in the beach photo above. How to shoot a star-shaped lens flare shows how.
Depth of field at 12 to 16mm
At the same aperture and focus distance, a shorter lens gives more depth of field, and at ultra-wide focal lengths it is deep enough that a single focus point can cover nearly everything. The quick way to use it is the hyperfocal distance: focus there and everything from half that distance to the horizon is acceptably sharp. On full frame, using the traditional 0.03mm standard for acceptable sharpness:
| Focal length | At f/2.8: focus at, sharp from | At f/8: focus at, sharp from | At f/11: focus at, sharp from |
|---|---|---|---|
| 12mm | 1.7 m, 0.9 m | 0.6 m, 0.3 m | 0.45 m, 0.2 m |
| 14mm | 2.3 m, 1.2 m | 0.8 m, 0.4 m | 0.6 m, 0.3 m |
| 16mm | 3.1 m, 1.5 m | 1.1 m, 0.5 m | 0.8 m, 0.4 m |
| 20mm | 4.8 m, 2.4 m | 1.7 m, 0.8 m | 1.2 m, 0.6 m |
Two things stand out. At f/8, a 14mm lens holds everything from 40 centimeters to infinity, which is why ultra-wide landscapes rarely need f/16 or f/22, where diffraction starts to soften detail. And even wide open at f/2.8, a 14mm lens focused about 2.3 meters away keeps everything from 1.2 meters to the stars sharp, which is what makes it the usual lens for night skies. The 0.03mm standard is generous for large prints on high-resolution sensors, so focus a little beyond the listed distance for a margin. For other sensors and apertures, use the hyperfocal distance calculator. When the nearest rock is closer than the “sharp from” distance, take two or three frames focused at different distances and blend them.
The flip side: an ultra-wide is a poor tool for blurring a background. Even at f/1.8, anything a few meters behind a subject 1 meter away stays fairly recognizable.
Where an ultra-wide earns its place
Landscapes with something close
A tidepool, a line of stones, a flower, a crack in the ice, a stream running toward the mountains: an ultra-wide lets you put that within a meter of the lens and keep the whole place behind it. A line that leads from the foreground toward the far subject ties the frame together, as described in leading lines. Without something close, an ultra-wide landscape is mostly sky and empty ground.
Rooms and tight spaces
Inside a small room, a car or a stairwell you cannot step back, so the angle is a necessity. Most rooms look true to life at 16 to 24mm on full frame. Wider than about 16mm, a small room starts to look larger than it is, and furniture near the edges stretches, which viewers notice and buyers of a house resent. Keep the camera level so door frames stay vertical, and see interior photography for light and height.
Buildings in narrow streets
An ultra-wide lets you fit a tall building from across a narrow street with the camera held level, then crop away the surplus foreground. Tilt the camera up and the uprights converge sharply; at these angles a small tilt looks like a mistake and a steep one looks deliberate. A tilt-shift lens shifts the view upward instead of tilting the camera, and architecture photography covers viewpoints and timing.
Night skies
A 14 to 20mm lens at f/1.8 to f/2.8 takes in a long stretch of the Milky Way with a landscape below it, and the short focal length lets a longer exposure pass before the turning of the earth smears the stars. The old rule of thumb, 500 divided by the focal length, gives about 35 seconds at 14mm; on high-resolution sensors stars trail visibly well before that, so stricter methods give shorter times. Settings and focusing on stars are in how to photograph stars.
People, carefully
A person in a place, centered and at least a meter or two away, works well: the setting tells the story. Close portraits and group shots with people at the sides do not, because of the edge stretch and the distance effect described above.
Need the width but not the stretched corners? Shoot several overlapping frames at 24mm or longer and stitch them; the stitching software can use a projection that keeps edges natural, as explained in panorama projections.
Common mistakes with ultra-wide lenses
- Using it to fit everything in. The result is many small things and no subject. Fix: pick one near thing, move close to it, and let the rest be setting.
- Standing too far from the foreground. A rock 3 meters away is a pebble at 14mm. Fix: halve the distance, then halve it again; half a meter is often right.
- Putting people or round things near the corners. At 14mm a face in the corner is drawn 84 percent longer than wide. Fix: keep them toward the center, or use a longer lens.
- Expecting a lens profile to fix the stretch. Profiles fix barrel distortion and dark corners, not the projection. Fix: compose for it when you shoot.
- A slight upward tilt. At these angles, a few degrees of tilt makes walls lean visibly. Fix: turn on the electronic level and zero it, or tilt boldly on purpose.
- Leaving the polarizer on under a blue sky. It darkens one part of the sky and not the rest. Fix: take it off or turn it to its weakest setting.
- Ignoring the edges. More than 100 degrees of view collects your feet, tripod legs, your shadow and stray branches. Fix: check all four sides before pressing the shutter.
Try this: the one-meter rule
Allow 10 minutes. Set your widest focal length (or the 0.5x camera on a phone) and, on a camera, f/8.
- Find a small object with some shape, such as a stone, a plant or a bag, with open space behind it. Take one frame from standing height 3 meters away, one from 1 meter, and one from about 30 centimeters with the camera near the ground.
- Stand in the middle of a room or a courtyard and take one level frame. Then take the same frame with the camera tilted up by about 10 degrees.
- Put a round object, such as a plate or a ball, in the center of the frame, then in a corner, without moving the camera, and take both.
How to judge it: in the first set, the object should go from a speck to something that dominates the frame while the background hardly changes; if the 30 centimeter frame still looks empty, the object was too small or you were not close enough. The tilted room should lean far more than the tilt felt. The round object should be clearly oval in the corner and round in the middle. If you can see all three, you have seen what an ultra-wide does.
Questions about ultra-wide lenses
What focal length counts as ultra-wide?
Shorter than about 24mm on full frame, which is about 16mm on APS-C and 12mm on Micro Four Thirds. There is no official line; some define it by angle instead, as 80 degrees or more across the frame. Below about 10mm on full frame, rectilinear lenses become rare and most lenses are fisheyes.
Is an ultra-wide the same as a fisheye?
No. An ultra-wide is rectilinear: straight lines stay straight and the edges stretch. A fisheye uses a different projection that lets lines bend, which squeezes the edges instead and lets it reach 180 degrees or more. A 15mm fisheye sees much wider than a 15mm ultra-wide.
Is the phone’s 0.5x camera an ultra-wide?
Yes. It sees roughly what a 13 to 16mm lens sees on full frame, and everything on this page applies to it. Phones correct barrel distortion automatically, but the edge stretch is still there, so keep faces away from the sides.
Why do my ultra-wide photos look empty?
Because everything far away is drawn very small, and the lower part of the frame fills with ground. Find something close, move to within a meter of it, and let it fill a quarter to half of the frame.
Should I buy an ultra-wide or a 24mm lens?
It depends on what you photograph. Rooms, night skies and landscapes with close foregrounds reward 14 to 20mm. Streets, travel and people are usually easier at 24 to 35mm, where edges stretch less and distant subjects stay a reasonable size.
Can I fix the stretched corners in editing?
Only partly. A lens profile fixes barrel distortion and dark corners but not the stretch, which comes from the projection itself. Some editors can re-project an ultra-wide image so the edges look more natural, at the cost of curving some straight lines; otherwise, crop or keep important shapes away from the corners when you shoot.