Manual Focus

Manual focus means turning the lens focus ring yourself to decide which distance in the scene is sharp, instead of letting autofocus decide. It matters because a camera only ever focuses on one distance, and there are subjects (a web, a star, a bee’s eye, a face behind wet glass) where autofocus picks the wrong one, or cannot pick at all.

For most of photography’s history, from the first cameras until autofocus arrived in the late 1970s, focusing by hand was the only way. It is no longer the main way, but it has never stopped being the right tool for certain jobs. Today it is also far easier than it was, because a mirrorless camera or a camera in live view can magnify the image and outline sharp edges for you. This page covers how focus works, how to set it by hand precisely, where it beats autofocus and where it does not, and how to measure your own accuracy in ten minutes.

One plane, one ring: what you are actually adjusting

A lens is sharp at exactly one distance at a time. Everything at that distance, across the whole frame, lies on the plane of focus, and turning the focus ring moves that plane nearer or farther. (Its counterpart inside the camera is the focal plane, where the sensor sits.) Nothing in front of or behind the plane is perfectly sharp. Some of it just looks sharp, because the blur is too small to notice. That zone of “looks sharp” is the depth of field, and how small the blur must be to count as sharp is set by the circle of confusion.

So manual focus is a targeting problem. The target is the depth of field, and its size decides how hard the job is. Here is how big it is in some common cases, worked out with the standard formulas for a full-frame sensor (circle of confusion 0.03 mm). Distances are measured from the sensor.

Lens and aperture	Focused at	Sharp from	Total depth
50mm at f/8	1.5 m	1.32 to 1.74 m	about 43 cm
50mm at f/1.8	1.5 m	1.45 to 1.55 m	about 9.4 cm
50mm at f/1.4	1.5 m	1.46 to 1.54 m	about 7.3 cm
85mm at f/1.8	1.5 m	1.48 to 1.52 m	about 3.2 cm
85mm at f/1.4	1.5 m	1.49 to 1.51 m	about 2.5 cm
Macro at 1:1, f/8	life size	0.5 mm either side	about 1 mm
Macro at 1:1, f/2.8	life size	0.17 mm either side	about 0.3 mm

Read the 85mm f/1.4 row slowly. A portrait at that setting has two and a half centimeters to work with, about the width of a thumb. Focus on the tip of the nose and the eyes are already going soft. At 1:1 magnification and f/2.8, the sharp zone is thinner than a credit card. If you want to try other combinations, the depth of field calculator gives the same numbers for any lens, sensor and distance.

To see how thin that target is, set a focal length, aperture and focus distance below and watch which figures in the row stay sharp and which go soft.

One more thing the table cannot show: sharpness does not switch off at the edge of the zone. It fades gradually on both sides of the plane. That gradual fade is why focusing by eye is hard. Near the peak, small turns of the ring make very little visible difference, so you need ways to see small differences.

How to focus by hand, step by step

This works on any camera with a focus ring and a screen or electronic viewfinder.

1. Set the zoom first. On many zoom lenses focus shifts when you change focal length, so frame the shot, then focus. If you zoom afterwards, focus again.
2. Switch to manual focus. Use the AF/MF switch on the lens or the focus mode setting on the camera. If you leave autofocus on the shutter button, a half press can undo your work.
3. Rough focus. Turn the ring until the subject looks roughly sharp at normal view. If peaking is on, turn until outlines appear on the subject.
4. Magnify on the exact detail. Punch in at the highest magnification your camera offers, centered on the one thing that must be sharp: the near eye, the brightest star, the edge of the petal.
5. Rock past the peak. Turn slowly until the detail goes soft, then back through sharp until it goes soft on the other side. Note where it was best on each pass and settle in the middle. Overshooting both ways is what tells you where the peak is.
6. Check at your shooting aperture. Some lenses shift focus slightly as they stop down. If you focused wide open but will shoot at f/5.6, check once more at f/5.6 if the camera shows the stopped-down view.
7. Do not touch the ring again. Then shoot, and check the result at 100 percent on the screen before you leave.

Want to rehearse this before you take a camera out? The camera simulator has a manual focus distance control, with peaking and a magnifier to check where the plane landed.

Focus peaking and magnification: one finds, the other confirms

Modern cameras give two aids for manual focus, and they do different jobs.

Focus peaking draws colored outlines on edges whose contrast passes a threshold. It is fast: you see at a glance which part of the scene is in or near focus, and you can watch the outlines travel across the scene as you turn the ring. But the threshold is the catch. Peaking does not mark the single sharpest distance. It marks every edge that is sharp enough to pass, so it lights a band, and that band can be wider than the zone that is truly sharp in the file.

How wide is the gap? One careful test with an 85mm lens at f/1.4 and 1.5 m found an acceptably sharp depth of about 15 mm (a stricter standard of sharpness than the table uses, which is why it is less than 2.5 cm). At its most selective setting, peaking lit about 21 mm. At looser settings it lit about 25 and then 39 mm. So even at its best, peaking would accept positions that were slightly soft.

Magnification (also called punch-in or focus assist) enlarges part of the frame so you can see detail at the pixel level. It is slower, because you only see a small piece of the scene, but it is the precise tool. The more you magnify, the narrower the range of ring positions that look sharp, so use the highest level you have.

The two work best together:

• Use peaking to get into the zone quickly, then magnify to find the peak inside it.
• Set peaking to its most selective level (the one that marks the fewest edges). The name of that setting varies between cameras, so test it: the right setting is the one where the outlines appear only on your subject, not across half the scene.
• Pick a peaking color that contrasts with the subject: red on a green leaf is hard to see, white on snow is useless.
• Expect peaking to struggle in dim light at high ISO, where noise creates false edges, and on soft, low-contrast subjects such as skin and fog.
• Peaking is only a display. It never appears in the saved photo.

Practise the find, then confirm routine in the simulator: switch to manual focus, turn on peaking, and focus precisely on the subject at f/2 or wider, where the sharp zone is thin.

If you use an optical viewfinder, you have neither aid there. The focusing screens in most autofocus-era viewfinders are made to look bright, and a bright screen shows blur poorly, so the image seems to snap into focus over a wide range. Older manual-focus cameras used dimmer screens with a split-image circle (the two halves of a line meet when focus is right) and a microprism ring (which shimmers until focus is right). On a camera with an optical viewfinder, switch to live view and magnify when focus matters. Viewfinders and screens compares optical and electronic viewfinders in more detail.

When manual focus is the better choice

Autofocus is fast, and for moving subjects it is usually more accurate than a hand on a ring. Manual focus earns its place where autofocus has nothing to lock onto, locks onto the wrong thing, or would move between frames when you need focus to stay put.

• Something between you and the subject. Branches, wire fences, rain on a window, and the bars of a zoo enclosure all give autofocus a near, contrasty target that is not the one you want.
• Thin or fine subjects against a busy or plain background. Webs, grass seeds, a single hair lit from behind. Autofocus often looks straight past them.
• Too little light or contrast. Stars, night scenes, fog, snow, a white wall. Autofocus needs contrast and light, and hunts back and forth without them.
• Macro. At high magnification the sharp zone is a fraction of a millimeter deep, and autofocus tends to land on whichever bit of the subject is most contrasty, not the bit you chose.
• Stars and other things at infinity. See the next section; the infinity mark on the lens is not reliable.
• Focus that must not change. Panoramas (every frame should share one focus distance), time-lapses, focus stacks and video, where autofocus moving mid-shot ruins the take.
• Lenses with no autofocus. Vintage lenses on an adapter, most tilt-shift lenses (and when the lens is tilted the plane of focus slants, so a single autofocus point could not place it anyway), cine lenses and many specialist macro lenses.
• Waiting for something to arrive. Pre-focusing on a spot where a bird will land or a cyclist will pass removes autofocus delay altogether.

The reverse matters just as much. For a child running, a bird in flight or a dancer, modern tracking autofocus will almost always beat you. And manual focus is not more accurate simply because it is manual: in the same test quoted above, a well-calibrated phase-detect autofocus matched careful peaking. Manual focus is a way of choosing where the plane goes, not a guarantee of sharper pictures. For a situation by situation comparison, see autofocus vs manual focus.

Is autofocus missing even on easy subjects? How to fix common autofocus problems works through the usual causes before you give up on it.

The lens side: rings, throw and the infinity mark

How a lens is built changes how manual focus feels and how far you can trust its markings.

Focus throw

Focus throw is how far the ring turns between the closest focus and infinity. A long throw, common on older manual lenses and on cine lenses, spreads small distance changes over large movements, which makes fine focus easy. A short throw, common on autofocus lenses because the motor can move faster, crowds the whole range into a small turn, so the last millimeter of focus is a tiny twitch of the fingers.

Mechanical rings and focus by wire

On a mechanical lens the ring moves the glass directly, so the same turn always gives the same change, and the lens holds its position when the camera is off. Many autofocus lenses instead use focus by wire: the ring is an electronic control that tells the motor what to do. The change can depend on how fast you turn, and some such lenses do not remember their focus position when the camera sleeps or powers off. On a tripod at night, check focus again after the camera wakes.

The infinity mark is not infinity

Many lenses, especially current telephotos and lenses with focus by wire, can turn past infinity. This allows for temperature changes and manufacturing tolerances, and it means that turning the ring to its stop, or lining up the infinity symbol, can leave distant stars soft. Focus on a bright star or a far light in magnified view instead. The infinity focus page and the guide to photographing stars cover the night-sky case in full.

Zooms, stopping down and breathing

Three things can quietly move focus after you set it. Many zooms lose focus as you zoom (set focal length first). Some fast lenses shift focus slightly as you stop down (check at the taking aperture). And on most lenses the angle of view changes a little as focus changes, called focus breathing. Breathing does not soften the photo, but it shows in video and in focus stacks. Lenses designed for video reduce it, though few remove it completely.

Pre-focusing: setting the distance before the moment

Manual focus does not have to happen at the moment of the shot. You can set a distance in advance and wait.

• Zone focusing. Set the lens to a distance, say 3 meters, choose an aperture that gives enough depth around it, and shoot anything that comes into that zone without focusing at all. With a 35mm lens at f/8 focused at 3 m on full frame, everything from about 1.9 m to 7.2 m is acceptably sharp. Street photographers have worked this way since the days of the rangefinder. Zone focusing shows how to set it up.
• Hyperfocal focusing. For landscapes, focus at the distance that makes everything from about half that distance to infinity acceptably sharp. See hyperfocal distance.
• Pre-focus on a spot. Focus on the branch, the finish line or the doorway, then wait for the subject to arrive.

Two camera settings blend manual and automatic focus. Back button focus moves autofocus off the shutter button, so the camera focuses only when you press the back button and leaves your setting alone otherwise. Many lenses also offer full-time manual override: after autofocus locks, turning the ring adjusts focus by hand without flipping a switch. Both let you use autofocus to get close and your hand to finish.

Manual focus in macro: move the camera, not the ring

At high magnification the focus ring changes magnification as well as distance, so turning it to fix focus also changes the framing. The better method: set the ring for the magnification you want (often at or near the closest focus), then move the whole camera slowly forward and back until the plane of focus slides onto the detail you want. A focusing rail does this in fine steps on a tripod. Handheld, sway gently and press the shutter as the eye or the edge of the petal comes sharp, and take several frames, because a body sway of a millimeter is already more than the whole sharp zone at 1:1.

With a depth of field of about 0.3 mm at f/2.8, it is often impossible to get everything you want sharp in one frame. That is where focus stacking comes in: several frames, each focused a little deeper, merged in software. The macro photography page covers lighting and gear for this kind of work.

Manual focus on a phone

Tapping the screen to focus is not manual focus. The tap tells autofocus where to look, and the phone still decides the distance. Many phone camera apps let you lock focus (often with a long press), which holds it while you recompose. True manual focus on a phone is a focus slider in a pro or manual mode, either in the built-in app or a third-party one, and some phones show peaking there too. Phone cameras have so much depth of field at normal distances that this is mostly useful for close-ups and for shooting through glass or foliage. The phone camera settings page covers the other manual controls.

Common mistakes with manual focus

• Trusting peaking alone. Peaking lights a band. If focus matters, magnify and find the peak inside it.
• Focusing at normal view. On a small screen almost anything looks sharp. Use the highest magnification available.
• Trusting the infinity mark. Many lenses go past infinity. Focus on a star or a distant light, magnified.
• Zooming after focusing. On many zooms that moves focus. Zoom first, then focus.
• Forgetting the camera moved. At 85mm f/1.4 you have about 2.5 cm. If you lean back a few centimeters after focusing, the plane is no longer on the eye. Refocus, or shoot from a tripod.
• Expecting stopping down to save a miss. Stopping down widens the zone, but at wide apertures and close distances it is still only centimeters deep, and stopping down changes the look you chose the wide aperture for.
• Leaving autofocus on the shutter button. A half press can refocus over your careful setting. Switch the lens to MF or use back button focus.
• Leaving the lens on MF. The next morning, the first shot of a moving subject will be out of focus. Switch back when you are done.
• Not checking the result. Zoom to 100 percent on the playback screen before you move on, especially for night and macro shots.

Focus spot on, yet still not sharp? Blur from a moving camera looks a lot like a focus miss; how to take sharp photos helps you tell them apart.

Try this: measure your own focus accuracy

This takes about ten minutes and answers a real question with your own camera: are you more accurate than your autofocus, and how big is the target you are aiming at?

1. Lay a tape measure or ruler on a table and angle the camera so it runs away from you at about 45 degrees. Put a small object, such as a coin, at one marking to be your target.
2. Use your longest focal length or your fastest lens at its widest aperture, about 1 to 1.5 meters from the coin. Use a tripod, or rest the camera on a bag.
3. Take three frames with manual focus, following the steps above. Turn the ring well away between frames so each one starts fresh.
4. Switch to single-shot autofocus with a single small point on the coin. Take three frames, defocusing between each.
5. On a computer, zoom each frame to 100 percent and note which marking on the tape is sharpest.

How to judge it. For each frame, write down how far along the tape the sharpest marking is from the coin, and multiply by 0.7: with the tape at 45 degrees, each millimeter along it is about 0.7 mm of depth. Then look up your lens, aperture and distance in the table above or in the depth of field calculator. The sharp zone extends on both sides of the plane, so if all six frames land within half the total depth of the coin, both methods are good enough at this setting. If your manual frames spread wider than the autofocus frames, magnify more and rock the ring more slowly. If the autofocus frames all land consistently in front of or behind the coin, the camera or lens may need adjusting; if your hand beats it, you have found a setup where manual focus is the better tool. Either way you now know, in millimeters, how big the target is.

Curious why the sharp zone is so much thicker at f/8? Aperture explains how the opening controls depth of field as well as light.

Manual focus questions

Is manual focus more accurate than autofocus?

Not automatically. With a still subject, careful manual focus and a well-calibrated autofocus land in about the same place. Manual focus wins when autofocus picks the wrong thing or cannot see the subject, and autofocus wins on anything that moves.

Why do my photos look sharp on the camera but soft on the computer?

The camera screen shows the image very small, so a near miss looks sharp. Check focus in magnified view while shooting and at 100 percent on playback. If the miss is the same in every frame, also rule out camera shake, which softens the whole frame rather than one plane.

Can I use manual focus with a lens that has no markings?

Yes. The markings only help with pre-focusing by distance. For focusing by eye, use magnification and peaking on the camera, which work the same with any lens.

Should I use manual focus for video?

Often, yes. Autofocus can drift or hunt during a shot, which shows in video in a way it never does in a still. Many video shooters set focus by hand and leave it, or move it deliberately between two marks. Camera settings for video covers the rest of the setup.

Does manual focus work with autofocus lenses?

Yes. Flip the switch on the lens or set the camera to MF. Many autofocus lenses also allow full-time manual override, so you can touch up focus by hand right after autofocus locks.

Why can I not get stars sharp at the infinity mark?

Because many lenses focus past infinity, and the mark is approximate. Magnify on the brightest star and turn the ring until it is the smallest, tightest point you can get, then leave it.