Spring 2012

Spring 2012
by ani

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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

9
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3answers
8k views

How to enable Canon AF with teleconverter?

Canon DSLR bodies prevent poor auto-focus performance by disabling it completely when the lens reports maximum aperture at chosen focal length smaller than f/5.6. This implies that some lenses will ...
2
votes
3answers
396 views

How to focus on fast moving objects with a low-end dslr?

I will go to an Enduro race and I want to take sharp, in focus, photos. I only have a Canon 550D, EF-S 18-55 IS and EF 50mm f/1.8. I tried using autofocus on moving motorcycles and 90% of them were ...
0
votes
1answer
224 views

Nikon D750 + Nikkor 18-35mm - How to enable full autofocus?

I recently got this powerful duet (before I had Pentax K-r), sadly I can call myself a total beginner even I used dslr previously... as I used it with auto mode. However I am learning slowly now, but ...
5
votes
1answer
106 views

Where can I find information on the Pentax Q lenses serial protocol?

I'm searching for detailed information on the Pentax Q lenses (any, but I'm especially interested in the 5-15mm-lens) serial protocol, which controls focus/zoom/aperture. So far I have found nothing ...
0
votes
1answer
71 views

How can I enable back button focus and disable focusing with shutter button on a Nikon D5500?

I assigned the AE-L, AF-L button to activate focusing on my Nikon D5500, but I can still focus using the shutter button. I would like to know if it was possible to use the AE-L/AF-L button to set ...
1
vote
2answers
534 views

Can I enable back-button focus on a 3rd-party battery grip for my Nikon D610?

I have set up my camera to have back button focus. Does this not carry over to the battery grip or is there a way to set that up as well. I have a Nikon D610 but I have a third party grip (vello ...
0
votes
1answer
37 views

Why does using the viewfinder on my Nikon D3200 prevent autofocus from locking and the shutter from releasing?

I just bought the camera less than a week ago and I was happy with it until things went wrong. I woke up one morning to take photos and noticed that when I pressed the shutter button, it didn't ...
0
votes
1answer
151 views

Apertures required to enable autofocus on Rebel T6s/T6i in Live View?

Your article "What apertures are required to enable autofocus, including cross-type or high-precision focusing, on Canon DSLR cameras?" is most useful. Would the new Canon autofocus technology, in the ...
3
votes
1answer
84 views

Nikon D5500 Autofocus with Sigma DG 150-500mm 1:5-6.3 APO HSM

Should the Nikon D5500 be able to auto-focus the Sigma DG 150-500mm 1:5-6.3 APO HSM lens? Auto-focus works with this lens on my Nikon D40X. On the D5500 it toggles between MF and AF. Video of what I ...
5
votes
2answers
4k 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
2answers
201 views

Is there any reason you would use one-shot focus over AI-Servo?

The only one I can think of is recomposition - achieving focus and then recomposing. Are there any others? The convenience of tracking your subject seems very, very convenient - moreso than the lock ...
1
vote
2answers
131 views

Nikon focus and recompose: identifying behaviour on different models

My Nikon D3000 refuses to take a picture if I focus and recompose with the AE-L/AF-L button set to "AF ON". (The focus point is on an out-of-focus part of the image after I recompose, so the shutter ...
5
votes
5answers
14k 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 ...
6
votes
3answers
4k views

Can I determine if an image was captured using Manual or Auto mode?

Is there a way to find out if a picture (once taken) was taken in Manual vs. Auto mode? My daughter is in a photography class and we both have taken images with the same camera. I sometimes put it ...
0
votes
3answers
83 views

Why doesn't focus confirmation appear in AI-servo mode?

Camera: Canon 700D Lens: EF-S 55-250mm STM So far I have been shooting still subjects. But recently I wanted to photograph moving people (skaters). I changed the AF mode to AI-Servo (as skaters are ...
1
vote
1answer
347 views

Pictures start in focus then go out of focus?

I was recently shooting some surf after a session with my 7d and Tamron 18-270MM F/3.5-6.3 Di II VC PZD. I started shooting while he was in focus, then as he got to the main part of the maneuver the ...
12
votes
1answer
390 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 ...
2
votes
1answer
44 views

How can I use AF+MF on Fujinon lenses with hard stop focus rings?

Fujifilm cameras have an AF+MF mode which autofocuses when the shutter button is half-depressed, then lets you correct it using the focus ring. However, some Fuji focus rings have hard stops, so you ...
0
votes
0answers
29 views

How do I lock focus in live view with a Tamron 17-50 2.8 VC on Canon?

How do I lock focus with my Tamron 17-50? I have separated the AF-ON button to lock focus, but when I move the camera to recompose the picture, the lens tries to refocus again. I see that this ONLY ...
0
votes
2answers
47 views

Canon 6D not taking pics in AF

I just got a used Canon EOS 6D and I have a Tamron AF 28-75mm F/2.8 Macro Lens. What I have noticed is that when I try to take a picture and have the lens switched to AF mode it won't work if I use ...
0
votes
2answers
79 views

What focusing points are used with a Sony A6300 camera + LA-EA4 lens adapter?

I'm about to acquire a Sony A6300 e-mount camera. I wish to use various A-mount lenses with it. Sony sell their LA-EA3 and LA-EA4 adapters to interface A-mount lenses with e-mount cameras. The LA-...
4
votes
2answers
2k 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 ...
0
votes
0answers
305 views

Which focus points on the Nikon D750 support f/8?

The Nikon D750 has 11 autofocus points rated up to f/8. Which ones are the f/8 points?
1
vote
1answer
78 views

Bad focus. Is it me or my body (D7000)?

So I have a D7000. Grey market, which I didn't find out until after I had to send it in to get serviced. And it's never felt as...sharp as it should be. I always assumed it was just me. I am going on ...
3
votes
2answers
2k 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 ...
6
votes
4answers
18k 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 ...
5
votes
3answers
7k 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 ...
1
vote
0answers
46 views

How can I increase my compact camera's suboptimal autofocus accuracy?

I own a Canon G1X compact camera which is quite good in my expectations, except that I cannot really be confident in its autofocus accuracy especially in non-optimal light conditions. Manual focus is ...
1
vote
1answer
96 views

How do I enable back-button AF on the 760D

I have an EOS 760D (recently upgraded from a 30D - yay!), and I'm can't find the custom function that allows you to use back-button AF. Does the 760D have this feature at all or has it been omitted? ...
0
votes
2answers
66 views

How can I improve my soft-focus shots out of a moving vehicle?

I was shooting with a shutter speed of 1/4000, f/7, ISO 800, using a 70-300mm telephoto lens. I have been shooting through the windshield of my SUV. Is there a filter I can use to help me get better ...
1
vote
0answers
64 views

Difference of auto-focus motor?

What is the difference of ultrasonic motor, stepper motor, and electromagnetic drive? Which one of these are lens-based or screwdrive? What are the advantages of lens-based servo over screwdrive and ...
2
votes
1answer
64 views

What are the (dis)advantages of moving the entire lens for focusing vs. only parts of it?

There's a lens adapter available that adapts Leica lenses to Sony mirrorless cameras. It's called TECHART PRO. The key feature is that it allows to use autofocus with the manual lenses. This works by ...
35
votes
4answers
64k views

What is back-focusing?

What is back-focusing? Is it something I need to be worried about, or can I just live with it? How can I tell if my camera/lens is sufferring from it?
1
vote
2answers
80 views

How do I disable autofocus on my Nikon with a Sigma 10-20, which has no manual focus switch?

Just purchased a Sigma 10-20 f/4-5.6 DC HSM lens. In attempting to capture astrophotography, the lens continuously tries to find a focal point in the sky, and doesn't. So I attempt to turn it to ...
0
votes
4answers
3k views

Why would my Tamron lens auto focus stop working?

I purchased a Tamron 70-300 mm lens for my Nikon d5300 a few days back. Its autofocus worked perfectly. But now it doesn't work at all. I am a beginner and I don't know much about it. Why would it ...
7
votes
4answers
316 views

Why does holding the focus and recomposing also affect the brightness of my photo?

Let's say I try to take a picture of the following scene: a nice, blue river on the bottom and a solid, grey building in the middle. It is a sunny day and I am in a large distance, so both "objects" ...
2
votes
2answers
234 views

What is the best focus setting for a group photo in manual mode?

I have a Canon 5D Mark III. I understand the depth of field issues taking group photographs at a wedding, but I am concerned the guests at the extremities might be less in focus than the centre if I ...
0
votes
2answers
194 views

Fast-focusing point and shoot camera?

I mainly take pictures of my grandkids playing, some scenery and birds. I am looking for an autofocus type camera that has a good zoom, one that will shoot quickly in low light situations. I miss a ...
1
vote
1answer
101 views

Can an off-centre AF point be as sharp/sensitive as a centre AF point?

What is the focal plane for an off centre AF point? Is it the same focal plane as centre AF point? Can off-centre AF point be as sharp focus as the centre AF point? If not, will the sensitivity of ...
9
votes
3answers
788 views

What motor gets used if both lens and camera body have a focus motor?

If both a camera body and lens have motorized autofocus, would one be used over the other or would both work in tandem to speed the focus process along?
18
votes
4answers
13k views

How do camera body motors compare to in-lens motors for focusing?

What is the difference between using a motor on the camera body and the motor built into lenses? Aside from how both compare in terms of speed, what differences would I notice if I use a body with a ...
0
votes
1answer
145 views

Why is my D7100's auto focus not working?

Recently my Nikon D7100 has stopped auto focusing. It's with the AF-S 50mm f/1.8G lens (my only lens). Yes, all the switches are set to auto, and I've done a reset. The autofocus assist light doesn't ...
1
vote
0answers
49 views

Autofocus not working on AF-S 35mm 1.8 DX with Nikon D3100

I haven't been using my camera very much over the past few months. The few times I've pulled it out, I noticed that the autofocus doesn't work when I put on my 35mm prime. I tested my 55-200mm and 18-...
3
votes
1answer
7k 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 ...
3
votes
2answers
187 views

How to more effectively stay in focus with a wide aperture (50mm/1.8)?

I've been experimenting with street photography lately and - while I'm getting some decent shots - my biggest pain point is staying in focus. For example: With the following subject, I nailed a ...
1
vote
2answers
99 views

How many autofocus points in iPhone 6 camera

I have seen that high-end SLR camera tout the number of autofocus points they have. How many AF points does the iPhone 6 camera have? I have not seen any discussion on it except for "focus pixels".
0
votes
1answer
57 views

Focus issue in D810 after repair

Just got my D810 back from Nikon repair for a USB port problem. The camera was reset completely, including all my settings, date, etc. It has the latest firmware. After doing my usual setup, I used ...
2
votes
3answers
147 views

Why isn't my DSLR focusing accurately on a fast-moving subject?

Here is a photo I took earlier today: I did my best to track him down the hill and fire off as many shots as I could. Some turned out fine and in focus but the better ones like this one didn't. My ...
43
votes
4answers
24k 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 ...
6
votes
1answer
1k 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 ...