Advice on D90 autofocus for sports

<p>Hi Everyone,<br>

For the last couple of months I have been shooting cross country runners at my son's high school events. I use a D90 with 55-200mm AFS VR lens, usually at about 55 to 90mm. I use single point focus (at the center) and dynamic focus. I try to pick up the runner with the center focus point, then follow him/her with multiple shots, then pick out the next runner.</p>

<p>I have slowly gotten better. I try to start when they are coming directly at me, which works pretty well, but this isn't always possible. Often there will be another runner in front of him/her until they get quite close to me. At that point they are moving pretty fast in front of me, and I don't think the AF can keep up.</p>

<p>Does anyone have any suggestions, other than the obvious practice, practice, practice?<br>

Thanks!<br>

Doug</p>

<p>I've gotten okay results with 3D tracking. Although it's not a "sports camera" it does okay for a 7-year old playing soccer.</p>

<p>I don't think the obvious answer is practice. Instead, neither the D90 nor the 55-200mm is designed to shoot sports. When a runner is coming directly towards you and he/she is getting close, it is quite challenging to the AF system because the focus is constantly changing quickly. I would say the obvious answer is to upgrade both camera and lens, but I am not sure that is what the OP is interested in.</p>

<p>Definitely stay with the center AF point on the D90. That is the only cross type it has.</p>

<p>Shun,<br>

I am considering a D300s or D7000. Which would you suggest?<br>

Also, what lens would you suggest. I assumed the AF on the 55-200 would focus about as fast as any others. Do you mean a f/2.8 or something for faster focus?<br>

I appreciate your responses.<br>

Doug</p>

<p>Many cameras have difficulty acquiring accurate focus when the subject is moving directly towards or away from you. Your camera will focus more efficiently and accurately if you are at a slight angle to the subject rather than straight on. I also suggest stopping your lens down, to f8, f10 or more. This will help you get more keepers as the DOF will be large and possibly compensate for inaccurate focusing.</p>

<p>I recently acquired a D50 and took some youth soccer pictures with it yesterday with the 70-300mm VR lens and the focus speed and accuracy were surprisingly good. I would image that the D90 would be superior to the D50 in the AF department so you should not have difficulty with your setup if you change your technique just a little bit.</p>

<p>Personally, I tend to steer away from dynamic focus on all the bodies I use unless I cannot get good focus with one focus point.</p>

<p>Except for a few people who got advanced samples of the D7000, nobody outside of Nikon has tried the D7000. Based on the specs, I would imagine the D300S has a better AF system, but I am sure the D7000 has much newer electronics that will perform much better in many ways, thus making it a difficult choice.</p>

<p>It semes obvious that the D300S will be replaced some time in 2011 (or perhaps earlier?). There are all sorts of rebates if you buy one with certain lenses.</p>

<p>Plastic mount lenses such as the 55-200 (any version) are designed to be inexpensive. If you want fast AF, I would buy an f2.8 zoom that lets more light in and has a stronger AF motor. Clearly not everybody wants to spend $2200 on the new 70-200mm/f2.8 VR 2. Either the older 80-200mm/f2.8 AF-S or version 1 of the 70-200mm/f2.8 AF-S VR are possibilities. The 80-200 should be below $1000 used.</p>

<p>Between the two, I would upgrade the lens first and see how it works on the D90 before upgrading the body. The D90 is still a reasonably new DSLR. Those f5.6 lenses are always a challenge for shooting sports.</p>

<p>Just some thoughts...</p>

<p>Have you tried using AF-On to separate the shutter release from the AF?</p>

<p>When you try to track something (I assume you have it set to AF-C) it's often faster when the focus is almost right before you start shooting. So you can pre-focus on the road or something else at the right distance. Then when your subject is there you start tracking him. Since the focus is more or less right from the start the camera will lock on much faster.</p>

<p>Using AF_On is more or less a must I think but YMMV.</p>

<p>I think AF-C on the D90 also means that you are in release priority which means that you can fire at will , regardless if the camera think it's in focus or not. It could be a good idea to check DOFmaster or similar what kind of DOF you have at the distance, focal length and aperture you use.</p>

<p>As Elliot mentioned I would also try thinking about the position you shoot from. It's not the speed of the subject itself but the relative movement required by the AF that makes thing more difficult. At an angle the focus distance will change slower than straight on. Also if you use a longer focal length you will be further away and the speed of the runner will be relatively slower.</p>

<p>I'd also try the single area AF mode and not the dynamic because it's faster in theory as it requires less calculations for the camera, if you can keep the AF sensor on the subject that is. In theory it also better for the camera when you shoot less frames per second as the AF can't focus during the time the mirror is up.</p>

<p>It may not make a difference depending on where the bottleneck in AF performance is but it's always worth a try.</p>

<p> </p>

<p>Hi Doug,<br>

As someone who shoots sports on a D90, I wanted to share a few thoughts...<br>

Running is a "linear motion" sport, like cycling. I photograph a lot of bike racing, but not running. (I will try soon; my 12-yr old niece is running cross country races every Friday.) "Random motion" sports like football, soccer, etc. require the AF system to acquire quickly. "Linear motion" sports require accurate tracking. I believe "linear motion" sports are easier to photograph.<br>

I started out trying to photograph bicycle racing on my D90 and had a pretty tough time in the beginning. My shots were generally soft. You can probably see a lot of older posts from me lamenting this problem and blaming my equipment.<br>

Then I met a few experienced photographers at races and they were quite helpful. I learned to keep the AF dot on the subject. I learned to move the AF dot with the thumbwheel (helpful if you are shooting a pack of riders and need to focus on the closest one). I also played around with different lenses.<br>

A pro photographer let me try his 70-200 f2.8 VR at a race. Instantly I was getting better shots. It just focused faster. Once I figured out how to get my shots sharp, we started swapping lenses. With a bit more practice, I am now able to get crisp shots with all of the following: 300 f4 AF (screwdrive, purchased in 1993), 70-300 f4.5-5.6 AF-S VR, and 105 f2.8 micro AF (also screwdrive, purchased in 1993). I can also do pretty good with the 18-105 kit lens. The 70-200 f2.8 is faster than all my lenses, but the 70-300, 300 f4, and 105 micro are good enough once I have learned to use them.<br>

The 700-200 is easier to use and what I really miss is the narrow depth of field. f2.8 will give me that. A zoom is essential for sports, so the 105 micro and 300 f4 have limited use. I just got spousal approval to go buy a 70-200 !!!<br>

I have not tried using the 55-200. One equipment-oriented website claims the 55-200 has slow AF and that the 70-300 is much faster. The author evaluates AF performance by photographing his 4-yr old kid. Whether the 55-200 is usable for sports would need to be verified in a real sports application.<br>

Fast lenses (wide f-stop, e.g. f2.8 not f5.6) focus faster because the AF sensor needs a difference between an out of focus image and an in focus image. I believe (guessing here) that you don't need a fast lens for running, but it sure would help. The 70-200 f2.8 would be awesome, but I'm guessing you can get it done with the 70-300 f4.5-5.6.<br>

my $0.02<br>

Allan</p>

<p>I have used the 70-300vr with good results..but as Chung states..if the lighting is not nice and bright..you could struggle a bit..it is a fantastic lens in bright light. I think the D90(which I own) is quite capable in most instances..but if you are a sports nut..and this is your love..I think you will eventually have to bite the bullet and go to a D300 or perhaps the new d7000. I use AF-C and dynamic focus on my sports shots(surfing)..and they seem to be ok for my purposes..strickly an amateur. Anyone out on the surf scene doing it professionally is using 2.8 lenses..and fast fast cameras..6fps or faster. I have read the 55-200vr is a bit slow for sports..but nice for other purposes. How about renting one of those 70-200vr lenses to try before you drop $$$ on new camera.</p>

<p>Hi All,<br>

I appreciate all your advice. I have noticed that the rig performs much better in bright light than dim, but the races run rain or shine (and the prettiest shots are in the woods.) I do understand the wide aperture zooms are going to focus faster, but needed the reassurance of your experience.<br>

Ideally, I do prefocus and try to shoot about 45 degrees to the runner, but when they are in a pack that isn't always possible. I think I will probably wind up investing in a new lens at some point, maybe after renting one (especially if it's the 70-200!)<br>

Thank you all!<br>

Doug</p>

<p>doug, i would probably get a new lens before a new camera, just because the 55-200 is not really up to the challenge, so you will have to upgrade this weak link anyway. if most of your shots are between 55-90mm, i would recommend the 50-150/2.8. it has a fast HSM motor which is much better than the 55-200's and will be stopped down to max sharpness at 5.6 and telephoto ranges, where the 55-200 will be wide open. with fast-moving subjects and a high shutter speed, VR is inconsequential, so you're not missing much (except $1400 saved) from a 70-200. the 50-150 does have instant MF override as well for fine-tuning focus. also, IMO the 50mm wide end is very useful on a 50-150; with a 70-200 or 80-200 you lose this critical range on a DX camera.</p>

<p>in any event, i would refine your shooting technique with the d90 in the meantime, using AF-On and working on selecting the best shooting angle for action. if you can wait until after the d7000 has been out for a little while, prices on used d300 and new d300s will drop. the d300s is already at $1400 new and the d300 is around $1000 used.</p>

<p>that's still a tough call vs. a new d7000, which does have more cross-type AF points and faster FPS than a d90, but a weaker AF system and less FPS than a d300s. if your main concern is sports photos, then a d300s makes sense, since the faster frame rate and better AF would come into play. however, the d7000 has newer tech and may have better low-light performance which would be useful for shooting other things than moving targets. ideally, you could try both at a retail store and determine if the d7000 will be good enough for sports. i suspect it will be decent in this regard, yet clearly not as snappy (with the right lenses) as a d300s.</p>

<p> </p>

<p>Eric,<br>

Thanks for the input. I agree that replacing the lens comes first. I hadn't considered the 50-150; that's a good suggestion. I have no experience with how fast the AFS is for non-Nikons. Most reviews concentrate on image quality, rather than focus speed.<br>

Doug</p>