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Autofocus is the ability of a camera/lens system to automatically adjust the focus of the lens via a motor attached to the focus group of the lens. Contrast with manual focus.

learn more… | top users | synonyms

5
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5answers
140 views

If I'm using only one focus point, am I doing it wrong?

Unless I have to shot a person or an object which moves, I set my camera to use only one focus point at the middle. It feels just more natural and so easy: when I need to focus on something which is ...
0
votes
1answer
168 views

What to do when autofocus on Canon 85mm f/1.8 not working?

My Canon 85mm's AF isn't working. But here's the thing, it recognizes there's a lens mounted, it gives focus confirmation, and I can even set the aperture, but it does NOT recognize that it's an AF ...
2
votes
3answers
297 views

What can I do when autofocus suddenly starts blocking at around 2m on a Nikkor AF-S 28-70mm 1:2.8 D?

I had this lens for quite a few years now, it used to work as expected. I didn't use my stuff for a few months, maybe 6-8 months. I just bought a D600 and tried to use them. The AF does not work as it ...
4
votes
4answers
3k views

Missing focus with Canon 50mm 1.8 lens - is it the lens or me?

I purchased a Canon EOS 650D and EF 50mm f/1.8 II lens. Unfortunately, the auto-focus seems to miss focus at f/1.8. I've tried setting it to single-point auto-focus: it is better, but still not good ...
8
votes
2answers
782 views

What technical reasons prevent Canon's new hybrid AF working with non-STM lenses?

Canon's new Rebel T4i (a.k.a. EOS 650D) has a new "hybrid AF" mode, which allows continuous AF during video, but only when used with one of the new STM lenses. I've seen chatter on the web forums ...
2
votes
4answers
12k views

What should I do when my Nikon AF-S lens won't auto focus?

I have a Nikon 35mm f/1.8G AF-S DX I bought for my Nikon D5100, it's only a couple months old, never been dropped or anything, and it all of a sudden won't auto focus. Anyone know if this is a simple ...
0
votes
1answer
23 views

Wireless Shutter Release Remote does autofocus before taking the snap?

I have Nikon D3000 and a wireless remote for it. I'm not sure about this thing: Suppose, I am keeping the camera on tripod where some birds will come. Then, I am setting my required zoom and other ...
1
vote
1answer
70 views

DSLR body without auto focus + auto focus macro extension tube set + lens without having auto focus motor but focusing screw = auto focus?

I've Nikon D3000. It died not have auto focus motor boot in its body. I've a lens having no auto focus motor within it. I saw some auto focus macro lens extension tube. Does that have autofocus motor ...
1
vote
2answers
105 views

How to focus manually with a Nikkor AF-S DX VR 50-200mm f/4-5.6G zoom lens?

I have a Nikon D3100, for which I just bought a Nikkor AF-S DX VR 50-200mm f/4-5.6G zoom lens. This is a CPU lens and works very nicely in auto-mode, i.e. when you let the camera set the focus. ...
2
votes
4answers
328 views

How to take a photo of defects on a mirror?

Taking a picture of a reflected image of object is depicted in this image. Camera focus is on the image of a piece of paper. Besides the depth of field (cheap Panasonic DMC-FX8 in makro mode, ...
0
votes
2answers
154 views

Does a Canon STM lens autofocus more quickly and accurately on a high-end camera body?

There are incredible reviews on the new Canon STM lenses: https://www.youtube.com/watch?v=ho0hOhRSuHk Does autofocus perform better on a 7D body, compared to an entry-level 700D body, for example? ...
5
votes
8answers
11k views

How can I focus in very low light with my Canon 60D?

I'm using a Canon 60D and would like to focus in low light. I know Canons — in fact, all cameras — can struggle here with auto focus, but I'm talking about light so low that I wouldn't be able to see ...
4
votes
2answers
104 views

What does it mean for a camera to be able to autofocus at EV 0 at f/2.8?

I know what it means for a camera to be able to autofocus at EV 0. As the answer to this question says, EV0 is the light level to achieve correct exposure with 1 second of exposure at F1 and ISO 100. ...
4
votes
4answers
4k views

What can I do if autofocus does not work but manual focus does?

Recently, the autofocus on my Nikon D3100 stopped working. The ring of the lens wouldn't even turn when I tried to focus. However, when switched to manual focus, the camera works fine. When I used a ...
3
votes
5answers
989 views

How can I make my Coolpix focus after I'm in place for a time-delayed self portrait?

I have a Nikon Coolpix S9100 camera I am trying to take few self-portraits by setting the self-timer and then going in front of the camera, however all the pictures come out very blurry. I am aware ...
-1
votes
2answers
144 views

Is it true that cameras with larger sensors are more likely to mis-focus under low light?

I use a Sony NEX-5R, and my single biggest problem with the camera is that it often mis-focuses under low light. I shoot a lot of low-light photos, and I work around it by using manual focus. I have ...
0
votes
3answers
153 views

What does the AE lock button do that half-pressing the shutter doesn't?

The Sony A6000 has an AEL button, while Nikon SLRs have an AE/AF lock button. What do these do that half-pressing the shutter to lock focus and exposure, and then recomposing, doesn't? I'm used to the ...
3
votes
1answer
2k views

Nikon D5100 Focusing Issue

The issue I have had is where the camera tries to focus and cannot focus. It just zooms in and out constantly and no matter what I do it will not focus and fire. The only way I have found around this ...
0
votes
0answers
23 views

AF points, focusing at f1.0-2.2 [duplicate]

I am considering the canon 5d mark iii or the 6d. Between the mostly negligible differences between those cameras, the AF point system of the 5d has many more "points". Having never really relied on ...
1
vote
1answer
453 views

Which Nikon DSLRs have an autofocus motor in camera body?

I have a Nikon D3000 and a lens which has no autofocus motor. But under the lens, I have found a screw which rotates with the focusing control. My D3000 does not have any autofocus motor inside the ...
1
vote
1answer
59 views

How can I confirm focus with a Nikkor 70-300 lens on a D3000?

Good day! I would like to have some suggestion from experienced photographers about following matter: I have a Nikon D3000 Camera. I bought a Nikkor Lens 70-300mm having not motor inside and unable ...
5
votes
0answers
164 views

At which lux level do the Nikon 1 cameras switch from PDAF to contrast-detection?

The Nikon 1 cameras are famous for being able to track focus with their on sensor PDAF. But the story goes that if light is low, it will switch to contrast-detect only and will not track focus as ...
5
votes
2answers
196 views

Why can't I access Single Point Spot AF even when it is enabled on my 5D Mark III?

I have been using Canon 5D Mark III since long but somehow never been able to get across this thing. With the advanced 61 point focus system which the Mark III has, I have always missed the ability to ...
1
vote
1answer
124 views

Focus in night photography

Another question related to the Olympus OMD EM5. I bought this camera to replace my Nikon D90 and I'm very satisfied with it. However, I find very hard to do the focus at night. With the Nikon D90, ...
0
votes
0answers
29 views

Nikon Lens Won't Autofocus [duplicate]

My Nikon Lens will manually focus but not auto focus. I have tried another lens on my camera body without issues and I have put this lens on another body and it will not auto focus there either. I ...
2
votes
2answers
218 views

How to tell whether a lens has an autofocus motor or not?

I have to buy a lens and I have a Nikon d7000. I want to know which lenses have AF motors and which do not, as the D7000 has an AF motor built into the body. How do I tell whether a lens has a motor ...
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2answers
83 views

Learning from one's blurred photos: where was the focus point set?

After some shooting, I inevitably find that some photos (and by Murphy, often the best ones) have a blurred subject. Even if the shots are spontaneous and hence the subject is hardly static, I ...
36
votes
3answers
10k views

What apertures are required to enable autofocus, including cross-type or high-precision focusing, on Canon DSLR cameras?

This is a follow-up to Why does Canon and Nikon limit or disable autofocus beyond certain f-numbers? I'm doing this to separate the AF aperture requirements from the linked question above. My goal ...
8
votes
6answers
488 views

Why is the main sensor not used instead of the separate AF sensor to focus a DSLR?

From this answer I understand that the reflex mirror of a DSLR is actually not reflecting all the light, but it passes a certain amount on to the AF sensor. So if the reflex mirror can pass light, ...
2
votes
2answers
225 views

Do separate autofocus motors exist for entry level Nikon DSLRs?

I have a Nikon D3200, which doesn't have an autofocus motor. Therefore, I'm mostly deterred by lenses that don't have focus motors in them. But the ones that do have it are much more expensive. Take ...
2
votes
1answer
476 views

How do I make the focus point indicators stay long enough to select on the Canon 60D?

I have just switched from the Canon 500D to a 60D. Most of my work is property based, and this is therefore 90% internal flash shots where I often wish to pick out a particular spot for best focus. ...
1
vote
2answers
120 views

Autofocus icon is missing in Canon 650D, please help

Can anyone please help me in getting this icon back in my canon 650d
3
votes
2answers
104 views

Why are phase detect lenses adapted onto contrast detect bodies so much slower?

The Sony A7 is able to adapt almost any type of auto-focus lens (Canon/Nikon/etc) and use autofocusing, but the auto-focusing is much slower than the same focal lengths native for the A7. Why would ...
2
votes
2answers
173 views

Why does my Nikon D5100 suddenly have a 30-60 seconds delay before auto focus starts working?

I have a Nikon D5100 with the 18-55 kit lens. It was working fine till a few days ago. The auto focus used to work from the very next second after turning ON the camera. But now the auto focus does ...
2
votes
4answers
262 views

Which one is better - more cross-type sensor or better sensitiveness of cross-type sensors?

What makes better sense for situations like: low light, sports/action, wild life? More cross-type sensor on AF (like Canon does) Or more sensitive cross-type sensors (like Nikon does)
11
votes
3answers
16k views

Will the Nikon D3100 autofocus with the 50mm f/1.8D lens?

I have the Nikon D3100 and was wondering if the autofocus on the Nikon 50mm f/1.8D lens would work with it. I've read that the AF is not compatible with the D5000, and that the AF is rather slow in ...
0
votes
0answers
31 views

Help is needed in Fixing Canon lenses USM's focus motor [duplicate]

I have the Canon EF lens, but the USM motor looks dead. I need help in order to get it fixed so I can use this lens again. Unfortunately a "focus by wire" system is used in this lens and I have no ...
0
votes
1answer
118 views

Why doesn't my Sigma lens autofocus if the subject is initially way out-of-focus?

I have a Sigma 150mm F2.8 EX DG OS HSM APO Macro lens mounted on my Canon 6D. Even if AF mode is set to minimum-to-infinity range, if my subject is way out of focus (too far or too near), like, say, ...
17
votes
3answers
934 views

Why don't cameras have autofocus points in the edges and corners?

On all the DSLRs I've used, there are never any autofocus points near the edges and corners. Why is that?
3
votes
2answers
2k views

Can a drop of a camera+lens cause AF calibration issues on either — or both — the lens and the body? What are the mechanics involved here?

My question is, if you drop a camera, and you think you might have an AF issue, what are the mechanics involved that might cause a mis-calibration? I can imagine that the lens has movable parts -- ...
1
vote
1answer
5k views

Why isn't my Canon 70D autofocus accurate in manual zone AF mode with a 50mm f/1.8 lens?

I recently purchased a Canon 70D for its dual pixel autofocusing system and ISO performance. I am in love with this feature rich-camera; however I found the camera's autofocus fails to function ...
3
votes
1answer
78 views

How to test the autofocus system before asking for support?

For outdoor usage I got an Olympus TG-2 compact camera. Various tests claimed autofocus: 'quick and mostly accurate' - at least I could not find any that described problems. Now, I know that I cannot ...
1
vote
3answers
247 views

canon 6d or 5d II for macro?

At the mo I have a 550d and a 60d. my lenses are 17-35 2,8L, 24-80 2,8L, 70-200 2,8L, 100-400 4,5-5,4L sigma 150 2,8 and looking for the canon 50 1,2. The obvious next step is a FF Body. My main ...
3
votes
3answers
154 views

Do focus area modes matter if shooting in manual focus?

It seems my camera lets me change the focus area modes (e.g wide, center or spot) even when I am shooting in manual focus so I am trying to understand if area modes matter even if the camera is in ...
0
votes
2answers
77 views

Nikon d7000 will not auto focus

Nikon D7000: When I press down on the shutter release my camera does not auto focus with any lens. I have checked and it's NOT on manual I have tried resetting my camera I want to shoot nightlife so ...
7
votes
2answers
2k views

If the focal plane is curved, should the outer AF points work correctly or front-focus?

Many (all?) lenses have a (slightly) curved focal plane. In general it's close enough to flat that you don't really notice it, but under certain conditions it may become apparent. As I understand it ...
3
votes
1answer
208 views

Do mirrorless cameras focus less or more accurately than SLRs under low light?

How do the following compare in terms of autofocus accuracy for night photography: Mirrorless cameras like the Sony NEX-5R, in hybrid autofocus mode. The NEX-5R, in contrast-only autofocus mode. A ...
7
votes
1answer
552 views

What are the differences between AF/metering chips for M42 lens Canon DSLR adapter?

I'm looking for an adapter to use an M42 lens on a Canon DSLR. I was wondering if anyone knows the difference between the following types of chips : 2nd generation AF 3rd generation AF EMF AF ...
1
vote
6answers
280 views

What would be the right way to shoot a portrait in a very dark room with flash?

I have several flash units. Both the shoe-mount type and the "studio" type. The portrait has to be taken in a room that happens to not have windows. It is always dark in there. I can bring a light ...
1
vote
1answer
154 views

What can I do about Pentax superzoom 18-270 autofocus problems?

I use a Pentax K200 and have been satisfied with the original Pentax 18-250 superzoom, for travelling, outdoors, family types of use. However the autofocus gradually failed, the motor going to and fro ...