D3's Autofocus 11.26.07
We come around a corner as we climb a ridgeline. The sun is playing dodgeball with a snow storm brewing in the west and at the moment, it's really dark. As we crest the ridge we come across a small bachelor herd of Bison, obviously the rejects of the breeding season. One of the bulls is right next to us and is sexually very frustrated, taking out his frustration on a scraggly sage bush. I jump out of the truck, 200-400VR with D3 attached comes with me. From the safety of being behind the truck I put the camera up to my eye. It's dark, the bison is dark but with a touch of the shutter release, the viewfinder is full of a bull's angery eye! After a few shots a spot light of sun hits the beast and the photo is made.
Damn, does the D3 AF, AF! This new generation AF system really works. It works better and faster than anything you've experienced in any other Nikon. It does come with a price (and I'm not talking sticker shock). Just when you think you might be mastering the Dynamic / Pattern AF system of the D2 family, we have a whole new system to learn and master in the D3. All the images you see in the D3 Gallery were taken using the D3's AF. No manual override was needed in the making of any of these images. The D3's system did it in a snap. That's pretty impressive to me. Even more impressive to me is that I've already made a couple of images that I otherwise wouldn't have had had I not been shooting with the D3. I wouldn't have had the images because they required the D3's very fast AF responsiveness and accuracy (the 9fps didn't hurt either). While I have the D3 AF working, I know I've not tapped its full AF potential. I also know that I don't have it all figured out to maximize it for every situation. Let me share with you what I've learned so far.
To start with, understand that the AF system in the D3 is basically brand new from the ground up, starting with the new Multi-CAM 3500FX focus module. This is how Nikon describes it:
"The D3 incorporates Nikon's new Multi-CAM 3500FX auto focus module that features an intelligent array of 15 cross-type sensors and 36 horizontal sensors. These sensors can either be used individually or in groups, with the option for Single Area AF mode and Dynamic AF modes using groups of either 9, 21 or all 51 focus points. The system also features 3D Focus Tracking with automatic focus point switching that takes advantage of all 51 AF points as it uses color and light information to accurately track the subject. Nikon's new Scene Recognition System and improved focus algorithms also contribute to the impressive performance of the new 51-point AF system."
What does this mean to you? Well, there's a lot of technology going to work for you, once you get through it all. Let's start with the AF sensors.
The D3 has 51 AF sensors that can be used either one at a time, or in a group of 9, 21, 51 or 51 3D-tracking. You make your AF sensor(s) selection in part via the AF mode selector on the back of the camera (CS#a3 determines the grouping when you select Dynamic AF). You can select via the AF Mode selector:
1)Single-point AF
2)Dynamic AF with 9, 21, 51 or 51 3D, or
3)Automatic-area (the silent wonder).
As with previous Nikon DSLRs, you select the desired AF sensor in which to focus by using the Multi Selector on the back of the D3. Here's a new twist to this, the Multi Selector moves the AF sensor diagonally as well as up/down, left/right. To facilitate AF sensor selection even more, you have Custom Setting #a8 where you can move through the various AF sensors to the desired one using just 11 of the AF sensors or using all 51 of them. In other words, to select the AF sensors you desire to use, you can peck around just 11 of the sensors, or all 51 of them. This does not affect nor is affected by whether you're using 1, 9, 21, 51 or 51 3D selected via the AF mode selector. Are you confused yet? Not to worry, easy to figure out if you have the D3 in hand. Here are the choices you can make in just the Custom Settings for AF operation to fine tune its operation to your style of photography.
a1 AF-C priority selection
Release
Release + focus (Moose preference)
Focus
a2 AF-S priority selection
Release
Focus
a3 Dynamic AF area
9 points
21 points (Moose preference)
51 points
51 points (3D-tracking)
a4 Focus tracking with lock-on
Long
Normal
Short
Off
a5 AF activation
Shutter/AF-ON
AF-ON only
a6 Focus point illumination
Manual focus mode
Continuous mode
a7 Focus point wrap-around
Wrap (Moose preference)
No wrap
a8 AF point selection
AF51 51 points (Moose preference most of the time)
AF11 11 point
In summation so far, to make the D3 AF work for you, you need to:
select the AF Mode desired (Single, Dynamic, Automatic)
select via CS#a3 the Dynamic AF area (9, 21, 51 or 51 3D)
select AF sensor movement (CS#a8)
This gives you a base in which to start exploring the other AF features of the D3. No kidding, this is just the starting point! Why do I say that? Let me explain where I'm at.
Currently I'm using the Dynamic 21 most of the time. With that being the case, I see in the viewfinder just 1 AF sensor lit up in red. The sensor is moved around until it's on the part of the subject that needs to be in focus. While we only see the 1 lit up AF sensor, there are actually another 20, yeah, twenty AF sensor around that one dealing with AF operation. You can see the AF "pattern" by depressing the Info button on the back of the D3. In the lower left corner you'll see what AF sensor(s) is active and the pattern (there is no longer one on the top LCD panel, Slot 2 icon has taken its place).
It took a little time to get accustomed to seeing 1 AF sensor yet knowing there are 20 around it working for me. Making the most of this system when photographing moving subjects has a little learning curve. Leading the subject like I did with the D2Xs/D2Hs isn't needed, neither is making sure the AF sensor stays directly on the original focus point. You could say that photographing action and getting sharp images is easier with the D3, once you make the technology work for you.
The first thing you're going to want to do is explore which Dynamic AF area works best for your photography. Not sure why anyone would use Single (which isn't Dynamic) when they just spend $5k for Dynamic 21 & 51. While 9 works, it really doesn't tap the power of the D3 AF system. Now when you get to 21, 51 and 51 3D, you're talking D3 AF performance. At this point in time, I've found the 21 Dynamic really makes the AF work for me the majority of the time. This is the mode I was in to take all the action photos you see in the D3 Gallery.
The 51 & 51 3D are frankly, still a slight mystery to me as to when to apply them in advance of action happening. I have played with both with the 51 & 51 3D with the 3D being very intriguing. While I've had mixed results using it, I have no doubt pilot error is the reason for that.
Let's talk about 51 3D for a moment. This might just be the ticket for photographing wildlife in action. Here's how I would describe how to use this new feature. You're photographing a Snow Goose flying against a blue sky. In 51 3D, place an active AF sensor on the goose. Once it has locked on, recompose however you desire. The D3 will keep the focus locked and track even though you might have totally the subject's placement in the frame. Pretty damn cool!
I would refer you to the great sports photographer (and really nice guy) Dave Black and his comments on this topic for more thoughts on 51 3D. Dave seems to have got it dialed in nicely.
The last click on the AF Mode Selector is the Automatic Area AF. Don't let the fact it has the giant single AF sensor icon of Nikon's past full you. This is a new AF function. When you flip the switch (AF mode selector) to Automatic Area AF, any Custom Setting you might have set for AF operation is no longer in play. Automatic Area AF (AAA) was explained to me as a kind of point & shoot mode in that you can lock your AF sensor on the subject and through subject recognition, it will track that subject while it is amongst other elements in the photo (this is different from 51 3D). Here to, I've had mixed results that I'm trying to resolve. It would be nice to have at the flick of a lever a faster "sudo" type of 51 3D AF than having to take time to set up through the menu (though you can customize My Menu to make it faster). While the two, 51 3D & AAA sound similar, they do work differently.
When it comes to moving the sensor around, I've gone to AF51 (CS#a8). The combination of the diagonal Multi Selector movement, Focus point wrap-around (CS#a7) and a little practice, moving around with 51 is pretty darn fast. While the 51 AF sensors don't cover the entire photographic area, they do a really fine job. But with all of this, how's the performance in the field?
While technically, the D3's AF shouldn't work in any darker light than the D2Xs, I find that it does. As I first blogged, my first interaction with the D3 AF was in a darkened room where the D3 with the 24-70AFS attached locked focus on a black pelican case. You still need a lens f5.6 or faster and you need the normal contrast/light for factroy standard AF operation, but I'm imrpressed with what I'm finding working outside those factory specs. I've found the D3 locking onto gray subjects in low, gray light in situations where before, I would have had to taken over manually focusing. For example, photographing a sunrise or sunset and the D3 is tilted up to minimize foreground and accentuate the sky. In this scenario, there is nothing but sky for the AF sensors to lock onto. It's not been an issue so far for the D3 even in the low light and contrast levels of sunrise, sunset. I've experienced very little AF "searching" with the D3 which is a real joy!
When it comes to grabbing onto a moving subject and "locking" on, the D3 excels there. That is due in part because of the new EXPEED/Scene Recognition System in the D3. In Nikon's words:
"Nikon's original Scene Recognition System, utilizing the 1,005-pixel RGB sensor, greatly improves autofocus, auto exposure and auto white balance performance."
To be honest with you, I'm not truly sure how this is working with the whole system. For example, does this work with every Dynamic mode or just the 51 3D? I wonder this because one photograph I captured was of a Rocky Mtn Bighorn ram chasing a ewe across a dirt slope. The ram and the background were the same color in the same light. I had run down slope when I saw the action coming at me. I was shooting with the 600AFS so getting both animals in the frame wasn't possible when they came around the bend running right at me. I got the ram in the viewfinder and just hit the shutter release and panned with it as it ran by. While looking through the viewfinder, I could have sworn the ram was out of focus, so I was really bummed. You know what I'm talking about, you've been there I'm sure.
I didn't even bother to chimp during the next lull to see what I had captured because I just knew they weren't sharp. Later that night on my notebook, I saw that the images were anything but out of focus. The entire series were all tack sharp. They were sharp! How in the heck did the D3 grab onto that ram against that background in that light, lock on focus and track? I honestly don't know but I want to find out. My hunch is that there is more going on that meets the eye, literally!
As more is learned, I will post it here so keep coming back. Look for the most the latest date to find out what I've learned using this incredible tool.
11.29 Update: 51 3D works on Color Recognition: AAA works on Closest Subject AND Color Recognition
I want to thank Bill Pekala & Carol Fisher at NPS and Lindsay Silverman for helping me navigate and master this very cool new AF technology!