# How good is Subject Tracking on higher end DSLR's



## globeglimpser (Dec 20, 2013)

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.




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.



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.


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## globeglimpser (Dec 20, 2013)

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.


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## jaomul (Dec 20, 2013)

I will say that I had many Canon cameras in the past and the upper tier models such as a 1d mark 2.With this camera I found it hard to "Miss focus" on moving subjects.
 By all accounts the later Nikons are even better if not slightly more complicated systems.I have just recently got a d7100. Have not had to much time to really check it out. The d7100 and d800 have similer (probably stripped down) versions of the d4 autofocus systems. A friend recently told me the Nikon d3s was king of autofocus until the 1dx was released (he shoots sports)


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## SCraig (Dec 20, 2013)

My personal experience using auto-tracking / 3D tracking / whatever tracking has not been good.  I've tried it while shooting birds in flight on 3 of my 4 Nikon bodies without very good luck.  If the bird has no background, as when shooting against a solid blue sky, it tends to work decently however if there is any background or if there are other birds in the frame (as with a bunch of Gulls) I have had a very difficult time getting the focus to remain on the subject.  It tends to go from subject to background or from one bird to the other.  It is probably just me expecting too much from the system but I get very frustrated when I try and use it and generally end up missing more shots than I get.  I finally just disabled it on the bodies I was using and have not even bothered to try it on my D7100.  Nikon's autofocus system is fast enough that I normally have no problems keeping a bird in focus using single-point continuous-servo autofocus.

Again, this is my personal preference and experience.  Others may have varying opinions and it is quite possible that I'm not using it properly.  All I know is that the system just plain does not work well for me.


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## robbins.photo (Dec 20, 2013)

SCraig said:


> My personal experience using auto-tracking / 3D tracking / whatever tracking has not been good.  I've tried it while shooting birds in flight on 3 of my 4 Nikon bodies without very good luck.  If the bird has no background, as when shooting against a solid blue sky, it tends to work decently however if there is any background or if there are other birds in the frame (as with a bunch of Gulls) I have had a very difficult time getting the focus to remain on the subject.  It tends to go from subject to background or from one bird to the other.  It is probably just me expecting too much from the system but I get very frustrated when I try and use it and generally end up missing more shots than I get.  I finally just disabled it on the bodies I was using and have not even bothered to try it on my D7100.  Nikon's autofocus system is fast enough that I normally have no problems keeping a bird in focus using single-point continuous-servo autofocus.
> 
> Again, this is my personal preference and experience.  Others may have varying opinions and it is quite possible that I'm not using it properly.  All I know is that the system just plain does not work well for me.



Well I use a lower end Nikon myself, the D5100 - and I have to concur with SCraig here, the autofocus "tracking" is fine, as long as you have a single subject with a high contrast background.  The minute you throw anything at the camera where it has to "pick" what to focus on the tracking thing pretty much goes out the window.  My camera is pretty old and the autofocus system is probably considered something out of the stone ages compared to something like a D610 or beyond, but at least in my experience  I've found my best results on my own D5100 have always been using the single point continuous servo as well.  If I have the time I can always change focus points or recompose, if I don't have the time I leave the focus point in the center and fix composition in post.


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## TheLost (Dec 20, 2013)

Maybe i'm a bit confused... my coffee hasn't kicked in yet.

But "Subject Tracking"?

Are you talking about holding the camera still (say on a tripod)..  focusing on a subject, then have that subject walk around (camera has not moved) and have the camera focus points move with the subject?

If so... that's kind of what 3D tracking does.  You focus on a subject and you can watch the focus point move around (or try to) as the subject moves around.  

Dynamic focus is "Single Point Focus" with extra help.  You put your focus point on the subject and half-press the shutter (or use AF-ON).  If the subject moves before you fully push the shutter the camera will try and follow your subject within your selected 'point range' (9/21/51 on the D7100).

IMHO... you should never let your camera track the subject for you.  YOU should track the subject and hope the cameras AF system can keep up.

The cameras with the best AF system.. (in order) would be:

D4/D3s
D800
D7100
D300s
D600/D610/DF
D7000/D5200/D5300
D3200

Also.. Keep in mind the lens plays a huge part on how fast/good your Auto Focus performance will be.  A slow focusing lens (like the Nikon 55-200) will have a huge affect on the outcome.


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## KmH (Dec 20, 2013)

Auto-focus has inherent limitations, and Nikon has a page in each of it's user manuals that notes some specific situations where AF will not work very well, if at all.
AF is not a be all to end all, and there are 2 kinds of AF - phase-detect AF and contrast-detect AF.

The AF points in the viewfinder are actually quite a bit smaller than the area the brackets in the viewfinder outline.
There are 2 type of AF points - regular, some of which only detect horizontal edges or only vertical edges, and cross type points that can detect both horizontal and vertical edges. Understanding Camera Autofocus

For tracking you want as many cross-type points as you can get, so that means you want a camera than has Nikon's prosumer/pro grade Advanced Multi-CAM 3500(DX), 51 point, 15-cross type points, AF module.
You would need to keep the subject matter within that group of cross-type AF points the camera has, and expect 3D tracking to stop as soon as one of the AF limiting scene situations occurs that Nikon describes in all it's manuals.

So scratch the Df and the D610 off your list if 3D-tracking is a main feature you want. They don't have the Advanced Multi-CAM 3500 AF module.
Note: the Df does not have an AF assist lamp.


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## Derrel (Dec 20, 2013)

Thom Hogan's just released Nikon Df review gives the camera high marks for focusing ability on moving subjects. Nikon Df Review | byThom | Thom Hogan

Excerpt: "Learn its nuances and you can get shot sequences that work nearly perfectly. I actually switched to my usual focus methods later to verify that they still work, but what I wanted to here is show here is that the 39-segment sensor is not exactly a slouch when left to its own devices (all auto). "

I have a D3x. Its focusing system is superb or moving subjects, or still subjects. But so was the 11-area, Wide-Area, 9 cross-type system in the D2x. It's not "just" the number of AF sensors that make a good focusing system.


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## TheLost (Dec 20, 2013)

I've played with the D600 and i thought its AF system was better then the D7000 (even though they are supposed to be similar).  It produced more keepers then i expected.

The downfall of the DF for me would be the 1/4000 shutter limit not the AF system


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## jaomul (Dec 20, 2013)

TheLost said:


> I've played with the D600 and i thought its AF system was better then the D7000 (even though they are supposed to be similar).  It produced more keepers then i expected.
> 
> The downfall of the DF for me would be the 1/4000 shutter limit not the AF system



Really- I don't think I have any shots faster than 1/4000th sec where the ISO was under 200. I better buy some faster lenses


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## Mach0 (Dec 20, 2013)

jaomul said:


> Really- I don't think I have any shots faster than 1/4000th sec where the ISO was under 200. I better buy some faster lenses



I haven't either. Then again, I haven't shot below 2.2. When I do, I use a nd filter.


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## Derrel (Dec 20, 2013)

I grew up with 35mm SLR's with top speeds of 1/1000. When I was in college, Nikon invented the first camera with 1/4000 second speed shutter, the Nikon FM-2. I seldom shoot much higher than 1/2500 second. I used 1/8000 second at f/2.2 at ISO 140 on one shot last summer, shooting a skim boarder and aiming RIGHT into the sunset at the ocean. Without a doubt the only time I've used 1/8000 second in literally years...
	

	
	
		
		

		
			





Even at only 1/1600, with a 300mm f/4 AF-S Nikkor prime, which has high image magnification, there's a lot of motion-stopping ability at 1/1600 second, at ISO 320, at f/4.5

 (you can see this much bigger here http://www.pbase.com/derrel/image/150150368   . THe Nikon AF  tracking is pretty good.)


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## Derrel (Dec 20, 2013)

Group Dynamic, using a multi-spot focusing group...Nikon's AF works GREAT. That is, IF you take a bit of time to learn HOW to use it that way it was intended to be used, meaning NOT with just one, single AF spot active, and the data from ALL THE OTHER AF SENSORS continuously being IGNORED 
	

	
	
		
		

		
		
	


	




.

200mm, f/2.5 at 1/750 second, ISO 640.






full frame capture, 1/1250 second at f/2.5, ISO 500.






Dusk soccer. 1/1500 second at 300mm at f/5.6, ISO 500. These are all down-sized pretty heavily, but you can see the larger-sized images here. These are all in good crisp focus. 

[  http://www.pbase.com/derrel/image/129370464  ]

http://www.pbase.com/derrel/image/129370467


http://www.pbase.com/derrel/image/50732151]


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## TheLost (Dec 20, 2013)

Youth football games.. early afternoon..  ISO 100.. 70-200 f/2.8 @ f/3.5..  i go over 1/4000 all the time.


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## Derrel (Dec 20, 2013)

TheLost said:


> Youth football games.. early afternoon..  ISO 100.. 70-200 f/2.8 @ f/3.5..  i go over 1/4000 all the time.



That's brighter than the Sunny 16 rule by a little bit...seems like you're wasting precious depth of field and focusing cushion by shooting at f/3.5...there's not a single play in youth football that needs 1/4000 second for motion-stopping. I'd be wayyyy more likely to stop down almost two stops and pick up better focus margin, and better image quality, rather than be shooting with paper-thin DOF and reduced IQ with the lens on 1/3 click down from max.

A low-velocity, "downloaded" .38 Special handgun bullet moving at a mere 385 feet per second was the bullet that Nikon stopped using the FM-2's 1/4000 second shutter speed back in their magazine ads in the early 1980s....I remember the ads they ran in all the magazines about how their new camera's 1/4000 speed could literally "*stop a speeding bullet*". I always thought that was kind of cheating though, since even a handgun bullet moving at 385 fps is VERY slow for a bullet; modern center-fire handgun rounds are typically in the 750 to 1,200 feet per second range, but hey...advertising claims, ya' know!.

I just wonder how we ever got along without 1/8000 second and 1/6000 second, you know, for the first 150+ years of photography...


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## runnah (Dec 20, 2013)

There has been only two cases where I have ventured into such high shutter speeds. Once when shooting an exploding hillside, and second when shooting an explosive welding technique.  

So yeah 1/4000+ is great for explosions.


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## Tee (Dec 20, 2013)

3-D focusing is my go-to method when shooting models.  I can set the focal point on their eye and if they move it tracks with them.  Definitely better than the focus and recompose method.


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## TheLost (Dec 21, 2013)

Derrel said:


> I'd be wayyyy more likely to stop down almost two stops and pick up better focus margin, and better image quality, rather than be shooting with paper-thin DOF and reduced IQ with the lens on 1/3 click down from max.



Sometimes i'm limited on where i can be..   If i'm 50 yards away and my lens is maxed out to 200mm @ f/2.8 i have a massive ~20 feet of focus depth. 







1/5000 | f/2.8 | ISO 100 | 200mm -- massively cropped

If somebody wants to give me a 300mm f/2.8 i'd have more options to get the subject isolation i want (or i move out of the sunny desert area i live now).  But until then my camera see's high shutter speeds all the time


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## yioties (Apr 25, 2014)

Not as good as staying on topic and not hijacking someones thread!


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