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.
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How do I keep my Nikon D5100 from attempting to autofocus with every shutter press?
I have a Nikon D5100 and the auto focus works fairly well most of the time. But there are times when I have a subject in focus and want to fire off multiple shots fairly quickly. I do not need to ...
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1k views
Are there cheap or DIY focus assist solutions for the Canon 5D?
I want a better autofocus system for low light. Low light auto focus is my biggest bane.
I use a 5D so the options are AF on a flash like the 430 or 580. I happen to use the Pocket Wizard TT1 so I ...
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254 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 ...
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662 views
AF-D vs AF-G: is the aperture ring necessary?
I just purchased a Nikon D7000 with an 18-105 f/3.5-5.6 AF-S lens. I'm also looking at purchasing a lens around the 200-300mm focal length range, and I found the 70-300mm f/4-5.6 AF lens. As far as I ...
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315 views
AF switch on lens vs. AF switch on camera
Is there any difference between using only the AF/MF switch on my camera (Nikon D90) or using the AF/MF switch on my lens (18-105mm)?
Could having autofocus on my camera switched to manual focus ...
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578 views
EOS Rebel T3i 18-55mm lens won't take a picture - happened with two lenses
I'm a reporter for a small town paper - Early in 2012 we had a body of a T3i go bad and it was replaced new body and we used the old 18-55mm lens. It worked fine for 7-8 months. I do a lot of sports ...
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245 views
Does having the AF points bunched up in the middle make a big difference?
I was looking into the new Nikon D600, which looks like a pretty compelling camera. I however noticed that its 39 AF points though quite a lot are all bunched up in the middle. I am used to having AF ...
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178 views
What autofocus zone selection mode should I use for action/event shooting?
I have a Canon 7D, and typically shoot everything I do in its single-point autofocus zone select mode, because I usually want fine control over exactly what the camera is focusing on and I often find ...
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2k 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 ...
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168 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. ...
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204 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, ...
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182 views
How much did the v2.0 firmware update improve the Fujifilm X-1 Pro's autofocus?
I really liked the Fujifilm X-1 Pro when I tried it for a couple of weeks — enough that it made me think seriously about switching from my much-loved DSLR about five years earlier than I thought the ...
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2answers
290 views
What's a Typical “In-Focus” Rate for Portraits with an 85mm?
I have a lot of experience doing travel, landscape, product, ... in short, things that don't move much. Models? Not so much. I have a beautiful 85mm portrait lens for my Canon 1Ds Mk III DSLR, and at ...
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625 views
Force AF assist light on body / flash to come on with Nikon DSLRs?
I have a Nikon D-40 and D-90 with a wide assortment of prime lenses. I like fast primes for low light photography.
Some of my lenses are sufficiently old that they do not auto focus at all. Others ...
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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 ...
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967 views
What causes auto-focus “freezing”?
On occasion, the auto-focus system in my camera and/or lens just stops working. I'll be holding down the shutter release halfway and tracking a subject and I can feel/hear the auto-focus system ...
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396 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 ...
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270 views
Do all cameras with autofocus need motors?
Do all autofocus cameras need motors to drive the lens? I would have thought today's modern electronics rendered motors obsolete.
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1k views
Which lenses typically don't focus properly on the Canon 60D?
I currently have the 18-200mm kit lens for my canon 60D. I am thinking of getting the 10-22mm wide angle lens as a second lens. So far with my kit lens I havent experienced any focusing problems or ...
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3answers
240 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 ...
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1answer
455 views
Why is my Canon Rebel T3i delayed 10 seconds or more before image capture?
I am brand new to photography and this camera. Had the smaller lens on and the shutter seemed fine. Tried the larger lens (I bought a kit) which was 200M. Played around with settings, also tried the ...
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3answers
398 views
Why are there no autofocus tilt-shift lenses? or, why do tilt-shift movements appear to be incompatible with phase-detection autofocus?
I have never seen or heard of an autofocus tilt-shift (perspective control) lens. It seems like perspective control movements prevent phase-detection autofocus from working correctly; for example ...
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2answers
308 views
Control and option comparison between the Nikon D7000 and the D300s?
I'm looking to purchase a new camera for both photoshoots and videos. I know all the technical differences like resolution, speed,...and all that. But I went to a shop where the sales lady told me ...
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338 views
What does this switch do on my macro lens?
There is a switch on my Canon 100mm USM Autofocus Macro Lens that switches between 0.32 mm and 0.48 mm (I think those are the numbers I dont have my camera near me). What do these numbers mean and in ...
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1answer
249 views
How can a teleconverter allow manual focus lenses to autofocus?
I've found that some discontinued teleconverters, such as the Pentax F 1.7x AF Adapter and Nikon TC16A, enable autofocus with manual focus lenses. How is this possible? Does this system have any ...
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2answers
117 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 ...
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1answer
121 views
Why isn't the gain on phase-detect autofocus sensors increased in low light?
Modern phase-detect sensors can focus in pretty low light. However, the limit for low light focusing tends to be reached much before the camera can no longer capture images using a high imaging sensor ...
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2answers
563 views
All my photos were blurry
I recently did a shoot of a baby and my 6 year old son, and I got some fantastic shots that were super sharp. I then did another shoot of a 6 year old and toddler and every single photo was slightly ...
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1answer
223 views
I almost cannot switch to manual focus on my Canon 17-40 f/4 L lens
Usually troubles with autofocus are related to a non working AF. I've got the opposite issue: AF is working too well. Actually, it is ALWAYS working, and I cannot turn it of.
Even when I switch to ...
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3k views
Are there solutions to limitations on using back-button AF on Nikon D3100?
I have started to use my D3100 with my AE/AF-L button set to AF. So in other words I use this button instead of the half press shutter button to AF. I'm new to this technique and came across it here ...
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173 views
lens care: compressing lens without full-time manual focus when camera is off?
The lens manuals for my lenses without "full-time manual focusing" warn not to use the focusing ring when it's in Auto-Focus mode. I assume that even applies when the camera is off, but am I being ...
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2answers
271 views
How To Fix Badly Functioning Shutter Release-Button?
I have a compact Pentax OptionM10 which I bought in 2006 and sometimes shutter-release button works only when pressing it on edge and under specific angle, but mostly as I apply little pressure which ...
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1answer
96 views
What factors influence whether a lens and camera combination front or back focus?
I know that sometimes a lens/body combo needs to be micro-adjusted to attain ideal focusing behavior, and that this is usually because of sample variation, but which parts of the lens and/or body are ...
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733 views
Is it really better to not half-press to focus with the Fujifilm X-Pro 1?
Fujifilm's new camera uses contrast-detect autofocus, and the current Internet hand-wringing is over whether this is a horrible critical flaw or not. As often happens in such discussion, a bit of ...
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1answer
240 views
When is it really necessary to use AF assist light?
I find the AF assist light to be distracting at times when I'm trying to take a candid shot without disturbing the human subjects or taking pictures of pets (they hate getting the AF light in their ...
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3answers
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Is the Canon 600D Al servo autofocus up to the task of following moving subjects?
Has anyone tried shooting fast moving subjects (birds, cars, running animals) with Canon EOS 600D using Al servo autofocus? I am thinking of getting this DSLR but the internet reviews are a bit ...
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618 views
Is focusing problems on Sigma lenses still a problem on a Canon body?
I am considering purchasing the Sigma 70-200mm f/2.8 EX DG HSM II Macro Lens. The problem is that many reviews point out that the lens has front focus problems, at least on a Canon mount. But those ...
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2answers
336 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 ...
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1answer
134 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 ...
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1answer
101 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 ...
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2answers
247 views
Enable Auto focus after timer on Nikon D800?
I'll start with an apology if everyone knows this but me.
I bought a Nikon D800 about a month ago (adore), but the wireless remote I used for the D7000 is not compatible. No worries, I'll just ...
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1answer
349 views
Why doesn't the focus assist light get triggered on a flash connected via a Pocket Wizard TT1?
I have a Pocket Wizard TT1 and TT5 which work fine. I mount the TT1 on the camera shoe and the TT5 fires my remote flash ETTL fine.
I now want a focus assist light, so I set a flash (580, 430 or ...
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1answer
152 views
How can one measure the autofocus performance of a lens?
Many of the lens reviews tend to comment on their autofocus performance, but they seem to be mostly subjective in nature (fast, slow, hunts around etc). I understand that the autofocus performance is ...
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409 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 ...
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5answers
383 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 ...
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2answers
284 views
Why is AF performance different in automatic and selective mode?
How often do you use AF in selective (SEL) mode?
The reason why I'm asking is that I've noticed that on a Pentax body (K10D and K-5) the AF is a lot more accurate when in AUTO mode than in SEL mode. ...
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2answers
232 views
How can I find which lenses have “Continuous manual focus”?
Canon lenses with USM auto focus can be called "continuous manual focus" (at least some). By this I mean that you can override the AF without switching it off. I've found this very handy, and I often ...
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4answers
265 views
Will the Nikkor 85mm f/1.4D be a good fit with the D60, even though it doesn't autofocus?
I've been using a Nikon D60 for over a year now, and thinking about upgrading the stock lens.
I am thinking about this lens:
Nikon Telephoto AF Nikkor 85mm f/1.4D IF Autofocus Lens
But on the page ...
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3answers
438 views
Is there a Canon equivalent for Nikon's AF-ON focus system?
I'm very new to photography, and have been reading a lot about concepts and techniques. Yesterday, my brother gave my kid a gift of a professional photography session. I saw the photographer had Nikon ...
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3answers
988 views
Why is AF slow in Live View on DSLRs?
Why is AF so slow in Live View on SLRs ? On compacts, the AF works very smoothly and quickly.
