Time to be with your loved ones

Time to be with loved ones

by sat

submit your photo


Hall of Fame
View past winners from this year

Please participate in Meta
and help us grow.

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

3
votes
2answers
1k views

Why is on sensor PDAF drastically slower than traditional PDAF?

Why is on sensor PDAF drastically slower than traditional PDAF? I assume the technology is the same, doesn't matter if the module is on the sensor or located behind a mirror. But the performance is ...
2
votes
2answers
567 views

Nikon D5100 intermittent focusing problem

I'm having this intermittent problem that the camera does not want to focus in auto-focus. When this happens I try to switch to manual on the lens, (both 300mm, and 55mm) but the toggle button will ...
3
votes
2answers
3k views

Do the issues with sharpness I am seeing require AF fine-tuning?

I own a nikon D7000 with 18-105 lens. I am not happy with sharpness I get with autofocus in portraits. I read about front/back focusing, but I am not sure whether my gear has this issue. Is this issue ...
2
votes
1answer
890 views

How can I make phase-detection AF more accurate with a Canon 650d and 50mm/1.8?

This is what I get pretty much every time when shooting in Live View mode using the Canon 50 1.8: This is what I get when I'm lucky when focusing through the viewfinder: This is what I get when ...
5
votes
3answers
4k views

Why does my Nikon D5000's AF Assist only turn on in some automatic modes?

I am using a Nikon D5000 with a 50mm f/1.4 with autofocus. When I try to use manual mode (or aperture priority, or shutter priority), my AF assist beam does not light, which makes it hard for my ...
2
votes
1answer
101 views

Does using multiple batteries (via grip) improve AF speed?

I want to say I read somewhere that, particularly with heavier lenses (such as the 70-200 F/2.8), having two batteries in the portrait grip would provide extra juice to the AF motor and help it ...
3
votes
3answers
531 views

Is focus hunting “normal behavior” for the Sony SEL18200SE?

I recently bought an NEX-6, the 24mm F1.8 (SEL24F18Z) lens, and the black 18-200mm F3.5-6.3 (SEL18200LE) lens. I love the 24mm lens, but I'm having a what I believe one would call a "focus hunting" ...
46
votes
4answers
12k views

What is the best way to micro-adjust a lens?

I have a Canon 7D with a 50mm f/1.4 lens, and I think the auto-focus of the lens is off. How can I test and adjust this reliably? Will this approach work with all of my lenses? If I had a different ...
3
votes
1answer
1k views

What settings affect how the focus points are displayed for my 7D?

My Canon 7d is about 2 months old. I used it for a shoot in DC, and it just isn't behaving as expected. When I try to focus, I get little black boxes in the focus frame. They used to be black, with ...
3
votes
3answers
2k 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 ...
2
votes
2answers
2k views

Do I use the camera or lens switch to change between auto and manual focus?

I own Nikon D7000 with 18-105mm lens. I am bit confused how the auto focus and manual focus switching works, particularly with my gear. The confusing part is both the camera and lens have an A-M ...
6
votes
3answers
619 views

Have I broken my Canon 28-135mm lens after DIY repair?

Last week I removed the front element from my Canon 28 - 135mm lens to remove a grain of sand from the lens. It was easy to remove the 4 screws, take of the top layer of glass and remove the grain. I ...
4
votes
2answers
2k views

What is the effect of the number of cross-type focus points on sharp focus?

Canon claims that EOS 6D has special capability to focus in low light, but it has only one cross-type sensor and overall only 11 focus points. Does only one cross-type focus point in the Canon EOS 6D ...
4
votes
4answers
3k 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 ...
5
votes
6answers
13k views

Why does my Nikon D3100 no longer auto-focus correctly?

I bought my camera on January 2011. Since a few months ago, I'm facing a problem with the autofocus. It happens with my two lenses 18/55mm and 55/200mm. I noticed that the focus light doesn't turn on ...
6
votes
1answer
557 views

What do orange AF points mean on a Canon DSLR?

I recently bought a Canon 7D and Ive noticed that occasionally the AF points are orange. What conditions cause this? It seems like it is a warning of some sort. Usually when the camera focuses on a ...
2
votes
2answers
245 views

Should Canon 5D mk II autofocus be accurate enough for a f/1.2 lens?

What autofocus accuracy can be expected from an EOS 5DII or EOS 5DIII camera? I have an EOS 5DII with f/1.2 and f/1.4 lenses. I have a lot of problems getting consistent autofocus with these lenses. ...
0
votes
3answers
2k views

How can I get better focus results with my Nikon D90 at a fashion show?

I shot at a fashion show last week, and had focus problems. I used my Nikon D90 with a Sigma 70-200mm f/2.8, with no flash. I tried many autofocus settings but none of them worked. I also tried ...
1
vote
2answers
2k views

Why are images with my Nikon D7000 and 70-200mm lens soft?

I'm having trouble getting sharp pictures with my D7000. I've tried it with a 70-200 and 18-70 and produce the same results. I've tried AF Fine Tune with one of those focus charts, but the value of 0 ...
6
votes
1answer
367 views

Where is the AF sensor located in a DSLR?

As I understand every DSLR has a separate, smaller sensor that handles phase detection focusing. Where is it located? If this location is different for every DSLR, and therefore this broad question ...
5
votes
1answer
1k views

Why does the IR-Assist beam of Canon Speedlites not get used in AI Servo AF mode?

The IR AF-assist beam on the Canon Speedlites (I have a 430 EX II) doesn't seem to come on when the DSLR (I have the EOS 7D) is in 'AI Servo' AF-mode. It works fine if I'm in one-shot mode (comes on ...
2
votes
5answers
2k views

Why my “action” shots are blurry even shooting on AF-C, is this a lens or camera limitation?

I'm currently using a Nikon 28-200mm AF-D with my D7000. While trying to take action shots (e.g. my dog running or sports) none of the shots seem to be in focus even on AF-C mode. Would this be a ...
12
votes
1answer
9k views

How does focus work on mobile phone cameras?

How does focusing work on mobile phone cameras? Aren't their optics simple enough to not have any moving parts whatsoever? If so, how come most smartphones have an auto-focus, and with various ...
1
vote
2answers
3k views

Why does Nikon D3100 locks Shutter in Autofocus mode?

So I just got this Nikon D3100 Camera. And I am trying to take a picture using autofocus with the kit lens(18-55mm). The system is in Auto mode, AF-A, single frame and the lens A-M switch is on ...
11
votes
3answers
3k views

Why do mirrorless cameras have quicker autofocus than SLRs using live view?

With early 2013 cameras, it's generally accepted that using contrast detection autofocus on SLRs (ie live view on most SLRs) is something which is really suitable only for static, or close to static, ...
1
vote
2answers
1k views

What kind of AF-motor does a Nikon D7000 body have?

I am a novice in the SLR photography world and am going to buy my first camera. I intend to take occasional videos. I guess if the AF-motor is screw and gear type, the clicking noise will ruin the ...
6
votes
3answers
15k views

Is the lack of AF Motor on the Nikon D5100 an important factor?

I had made up mind on purchasing a Nikon D5100 during the holidays but only yesterday I realized that it doesn't have a AF motor with it. This is forcing me to change to Canon 550D which is in the ...
0
votes
1answer
75 views

Will a shutter half-press perform an autofocus while shooting video on an EOS 650D?

Have Canon kept this feature or has it gone like the movie cropping mode?
2
votes
1answer
199 views

Why is my ISO so high in auto mode?

New user of a Canon 7D - less than 50 shots taken. Last night, I needed to take a quick picture of something that was on my cell phone with my Canon 7D I propped the phone up against a white pillow ...
5
votes
2answers
874 views

Can't auto-focus at full zoom

I have a Canon 1000d, and the standard lens EF-S 18-55mm. Recently I was out taking photos and I've noticed that if I zoom in fully, the lens can't auto focus. I can still take shots using manual ...
5
votes
3answers
407 views

Do I need a better Camera or do I need to learn how to use the one I have?

Read some of the old questions. I figure that due to my wants you may be able to help me. Let me be clear about what I am doing, what I want to do, and see where we can go from there. I help run ...
3
votes
2answers
1k views

Is it safe to manually-focus the Nikon 18-105 while in autofocus mode?

There are only A and M settings, no A/M. but I just noticed that Nikon website has mentioned three focus modes for this lens: Auto, Manual and Manual/Auto I'm confused if this is only a typo or is it ...
2
votes
2answers
1k views

Why is my Canon 500D with kit lens having trouble focusing at higher focal lengths?

I have a Canon 500D with the kit lens. Recently I have observed that its not able to focus at higher zooms but it works at min zoom. To get it to focus, I have to zoom out or recompose and it works. ...
1
vote
1answer
130 views

Can I use a Cosina AF 28-300mm f/4-6.3 with a Nikon D5100 if I focus manually?

The Cosina AF 28-300mm is an autofocus zoom for Nikon F-mount (body must have AF motor). Can I still use it with the D5100, provide that I will have to manual focus?
21
votes
9answers
3k views

Why would I want to select an autofocus point?

I'm trying to understand why I would ever want to select an auto focus point other then the center point. I have a Canon XTI Rebel DSLR which has 9 auto-focus points, but I'm also looking into getting ...
2
votes
2answers
473 views

How to improve the PowerShot G12 shooting speed?

I have been using a Canon PowerShot G12 for about a year, and find it incredibly slow. In full auto-mode, with good lighting conditions, I feel the G12 regularly takes close to 0.5 s between the time ...
4
votes
2answers
357 views

Can I control if the in-body AF motor is used instead of the lens AF motor on my Nikon?

I have Nikon D7000 with 18-105mm. I know that the camera body has the AF motor and the lens itself has the AF motor too. I was wondering can I control which AF motor should be used while autofocusing. ...
4
votes
2answers
3k views

Could autofocus of the Canon t4i be improved with a firmware update?

I am trying to decide between the Canon t4i (650D) and the t3i (600D). Initially I was going for the t4i because of the autofocus. But the sample videos I have seen did not really impress me. Can I ...
4
votes
2answers
875 views

What is the “AF Stop” button on some Canon lenses?

When looking at custom functions in Canon camera manuals, I've come across mention of setting functionality to have happen when the "AF Stop" button is pressed - a button that, apparently, exists on ...
6
votes
2answers
969 views

How does the eye-controlled focussing of the Canon EOS 5 work?

I just read that the Canon EOS 5 had eye-controlled focussing. How does this work? In this short article I found that it had to do with the coupling of infrared eye-tracking and the AF-point choice, ...
3
votes
1answer
213 views

Why 5-50x focal length for autofocus micro-adjustment?

When we do an AutoFocus Micro Adjustment session, the general opinion is to set the focusing target at 25 x focal length (or somewhere in the range of 5-50 x focal length). Why is so? What happens if ...
-1
votes
2answers
4k views

Automatic autofocus on 600D/Rebel T3i during video mode [closed]

I was testing the video mode with my 600D, and I noticed autofocus was not working. I then enabled it via the menu and now you can focus when pressing the main button. I was wondering whether this is ...
3
votes
1answer
140 views

Is it normal for live view to freeze when focusing with a point & shoot camera?

I went to a Best Buy recently and tried a few point-and-shoot cameras, among which the Canon G15, Canon SX260, and Canon SX50. With all of them, I noticed that the live view freezes for a short time ...
1
vote
4answers
2k views

Why can't I take a photo in dark with auto focus, manual mode?

I'm dorking around with a Nikon D80 and I am a total beginner. I am trying to shoot some light trails but the darn thing doesn't even take a picture. I am in manual mode with the bulb setting. For ...
1
vote
0answers
246 views

Why can I not disable full-range auto-focus in newer point-and-shoot cameras? [closed]

I owned a number of Canon PowerShot cameras (SD300 and SD1000), and I was always pleased with being able to quickly take one out of the pocket, and take a picture within about 2 seconds of noticing ...
2
votes
1answer
559 views

Canon T2i doesn't seem to take crisp photos

I've been using my Canon T2i to do portraits for the last year now, and usually have really good luck with it. Most of my shots are up close, and turn out beautiful. However, it seems like when I ...
2
votes
1answer
602 views

Why does my D70s no longer focus my Nikkor 70-300, but still focuses the 18-70?

At first I thought my lens was dead but after switching to my other D70s it worked fine. So, here's the issue: One of my D70s bodies can no longer auto-focus my Nikkor 70-300 lens. Switch to a 18-70 ...
10
votes
1answer
280 views

When focusing in Live View, where is the point of focus?

I use Canon SLRs. When using live view focusing, there is a rectangle which turns green when the focus is achieved. My question is: Is there a single focus point at the center of the rectangle? Or ...
6
votes
2answers
130 views

Can I intercept and interpret the autofocus signals sent to the lens?

I would like to use a Nikon D80 body with a reflecting telescope as the lens to take pictures of bright/textured objects in the night sky (e.g. the moon). The D80 has autofocus capabilities; the ...
8
votes
1answer
250 views

How do repair shops fix focus shifts on bodies lacking focus microadjustment feature?

For camera bodies without autofocus microadjustment capability, how do repair shops calibrate a specific body and a lens combination suffering from the focus shifts (back and/or front focusing)?