Before the rush

Before the rush
by evan-pak

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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.

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Nikon D60: Autofocus of two AF-S lenses not working anymore after using another lens

I have used my Nikon D60 for about 6 years now, with AF-S DX NIKKOR 18-55mm f/3.5-5.6G, and AF-S 55-200mm Nikkor f/4-5.6G lens, and the autofocus has been working fine this entire time. However, I ...
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1answer
408 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
1answer
116 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 ...
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1answer
157 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 ...
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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 ...
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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 ...
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0answers
56 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-...
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0answers
76 views

Canon 6D Auto Focus Erratic Behavior

I have a 2 year old Canon 6D which I use primarily for landscape photography and taking shots of my grandkids. It exhibits a strange behavior at times when I lift it to my eye to compose a shot. ...
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0answers
73 views

Manual and Autofocus not working on near field with Canon Rebel T3

I dropped my camera on a tile floor the other day and everything appeared fine. My wife tried to take some close up pictures of a gift today and found that the Auto Focus wouldn't work on close field ...
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0answers
109 views

What would cause an AF confirmation light to go on and off as I approach correct focus?

I'm using two cameras: Canon EOS 400D (Digital Rebel XTi) and Canon EOS 450D (EOS Rebel XSi). 450D was more heavily used than 400D. Not so long ago I noticed that 450D's autofocus system works not ...
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0answers
31 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 ...
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0answers
41 views

What is the 4D autofocus and how is it different from the continuous servo in Nikon?

I just saw a new auto focus term 4D focus introduced by Sony in one of their cameras. How is it different from the continuous servo in Nikon ? Are both the same ? or totally different ? And what ...
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67 views

Using manual focus ring on AF lens

Help... I have a Nikon D800E with a 70-200mm F2.8 My question is this, if I have both my camera and lens set on AF ,why do I still have to use manual focus ring to get clear focus on my subject???
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227 views

Are there any known focusing issues for the Nikon 70-200 2.8 VR and if so, how to compensate for them?

I have recently rented this lens for my D610. I feel that it is just off when auto-focusing? Takes kind of long to focus and does not always seem to focus on the subject I am trying to get in focus. ...
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0answers
315 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?
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0answers
172 views

Contrast detection AF not working?

What are the possible reasons why my Nikon D3300 won't focus properly at all on live view? It works perfectly when using phase detection (or when looking through the viewfinder), but when I start ...
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0answers
85 views

Nikon zoom lens troubleshooting

My Nikon D5100 squeals and won't photogragh on its 55-300mm lens beyond 80mm. I've tried turning autofocus on, taken out & reinserted battery, and changed memory cards.
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73 views

When does the Sony NEX-5R use release priority?

As I understand it, focus priority delays the shot till focus is achieved, while release priority potentially takes a mis-focused shot. Wikipedia says that release priority is usually used in ...