How good is Subject Tracking on higher end DSLR's

I am speculating over the following models: DF, D610 (39-focus point system), D7100, D800 with my heart leaning towards the DF.

However, I wanted to know from anyone with subject-tracking experience how good the subject tracking on these cameras is? I am thinking about focusing through a burst with a moving subject.

Once you put the camera in AF-C, you have 4 options: Single Servo, Dynamic, 3d and Auto Area (I am not so interested in the first or the least)

Dynamic Focus:

Nikon on the D610: Suitable for a moving subject. The camera will focus based on information from surrounding focus points if the subject briefly leaves the selected point. Dynamic-area AF allows you to choose from 9, 21 or 39 points. In each mode, the selected AF point and the surrounding points cover a wide area to keep your subject in sharp focus, combining with AF-C (continuous-servo AF) of autofocus mode.

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From my understanding, the camera will focus using the selected point and will the refocus using whichever point the subject moves to. Additionally, based on the fact that these points cover a "wide area", is it safe to assume that they can follow the subject even if it leaves the focus cluster altogether? If so how far can it go? To the edges or perhaps to the intersections of the thirds-lines?

Nikon on the D7100: Suitable for capturing moving subjects. Select one of 51 points as a priority focus point. If the subject briefly leaves this selected point, the camera will focus based on information from the supporting points surrounding it. The number of points employed in focusing can be selected from 9, 21 or 51, depending on the situation, such as movement of the subject and predictability of the movement. For all these options, the camera uses the selected and surrounding points to recognize the subject as an area, and continues focusing on the moving subject accurately in combination with continuous-servo autofocus (AF-C) of lens servo.

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By the looks of things, the D7100 would track in the same fashion? Only better since those points cover a greater area...

3D Focus:

Not something I use often on my D5100...

Just curious how it works and how good it is. What is the difference between this and Dynamic Focus? Which would be used for what purpose and which is more reliable?


Conclusion

Hopefully I can get more info on these two Af-C modes on the higher end cameras. Also if I missed something vital like another mode or setting which is critical in subject tracking, please do comment below.

I apologise for all the questions but I really do want to make an informed decision. Of course I will fully test a demo model my self to confirm everything pre-purchase but until then, it would be great to hear from some users what their experience is.

Perhaps I should add some context: I shoot a lot of street photography and would love the low light advantage of a Full Frame. I also wildlife photography and am interested in giving sports a go hence I need something with the focus. The D4 would be perfect but alas I could never afford it.

I am leaning towards getting a DF now since it would be beautiful for street usage.

I would the pick up a D7100 before a wildlife trip and it could also serve as a back up (problematic considering I have a few primes and so the focal lengths are all different grrrr)

But the advantage of this is that I would have 2 cameras for wildlife photography which is a great for getting portraits and environmental shots without changing lenses.

globeglimpser said:

I am speculating over the following models: DF, D610 (39-focus point system), D7100, D800 with my heart leaning towards the DF.

Conclusion

Hopefully I can get more info on these two Af-C modes on the higher end cameras. Also if I missed something vital like another mode or setting which is critical in subject tracking, please do comment below.

I apologise for all the questions but I really do want to make an informed decision. Of course I will fully test a demo model my self to confirm everything pre-purchase but until then, it would be great to hear from some users what their experience is.

Click to expand...

I have not used the D800 on extreme AF scenarios except when I shot some HS football at night which I think it performed very well using AF-C mode. I use single AF point if that matters with you and focus priority.

I've used the D700 before and for fast moving subjects, the AF of the D700 performed very well. Of course the lenses also played a great deal of faster AF.