Question about Nikon group focussing method

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boff180
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Re: Question about Nikon group focussing method

Post by boff180 »

Never seen that advice being given on here if it had it would have been challenged. After testing I never used group AF or 3D AF on any of my Nikons as it doesn't seem to give accurate results.

Instead of accurately metering focus at a set one point (and changing it as needed dynamically) area assesses multiple points to try and guess what you want to focus. 3D is fine until a low contrast situation then it struggles.

The best results for me come from AF-C set to Dynamic Area with all the other fancy settings turned off.

Andy

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aviationphoto
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Re: Question about Nikon group focussing method

Post by aviationphoto »

I use an oldish D300s (and even more ancient D200!) and I do use the dynamic area AF - settings for the D300s are:

AF-C priority: focus
Dynamic AF: 9 points
Tracking with lock on: long
AF activation: AF-ON only (using back button to focus)
With exposure compensation at 1/3 rather than 1/2 I usually shoot props at at 1/250th or 1/320th, helicopters at 1/160th and jets as fast as I can get at the selected ISO!

I do get a high proportion of shots sharp but I also see a lot of degradation if I crop in too much, even if the subject is sharp. If you are going to OW Sunday a 80-400 will be more than enough to get frame filling shots most of the time so hopefully this will make a difference.

Cheers
Andy
http://www.aviationphoto.co.uk

The Dark Rider is coming!! - check out my debut novel on Amazon

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aviationphoto
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Re: Question about Nikon group focussing method

Post by aviationphoto »

I was dubious about back button focusing when I first read about it and, on the surface, it doesn't seem to offer any technical advantage. However, since using it my aerial pics have been consistently sharper, particularly during high fps bursts. As for the exact reason I would leave this to someone more technically minded to explain as the only thing I can think of is that when using the shutter only, the camera is not focusing during the point the shutter is firing while with the back button it is focusing (and predicting) continuously no matter what the shutter is doing. I could be completely wrong though...

Best to give it a try and see if it works for you.

Cheers
Andy
http://www.aviationphoto.co.uk

The Dark Rider is coming!! - check out my debut novel on Amazon

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