Fast prime vs. expensive zoom for indoor sports photograhy?

Question

I plan to try shooting my kids' indoor activities (Tae Kwon Do and Figure Skating). I can get pretty close to the action for TKD, and I have access to ice/board level positions for shooting at the rink. Lighting in both cases is not great, but not terrible either.

While I would love to pickup a 70-200mm F2.8 (or even an older 80-200mm F2.8 without VR), it is fairly expensive (even used), and am wondering if I can cheat a little by using a fast prime and get my "zoom" (if necessary) by cropping after the fact? I was thinking of an 85mm F1.8 or something similar.

I would be using a Nikon D90. Is using a fast prime a workable compromise?

If I have to buy the fast zoom, one concern I have is that many reviews say they are "soft wide open", which I take it to mean that they aren't as sharp at F2.8. But if I have to stop it down for sharpness, then I lose shutter speed, or have to bump ISO, which is not going to help get better action shots. With an F1.8 (or F1.4) prime, I presume I would have the sharpness wide open and be able to reduce ISO or use a faster shutter.

Answer 1

Executive Summary: I really like the prime over the zooms.

I've shot Hapkido (very similar to TKD) using an 85mm f/1.8 prime and with a 60 mm f/2.8 prime on a D200 and D70-- the D90 has better lowlight capabilities than those two cameras.

Here's the 85mm on the D200 at f/2.5:

This might be a bit of a cheat, however, since there was light from the outside and bright fluorescent lights. Your kids' do jang might not be so well lit.

And for basketball for my niece, I went with the 50mm f/1.4 (used for $100). The lighting in that gym was terrible. I shot ~150 shots, and only one was close to being a keeper, the lighting was so bad and they just moved too quickly to get anything. I haven't shot figure skating.

1. I have many sparring shots where 1/250th of a second just isn't fast enough. When the impact comes, it comes quickly, and 1/500th or faster is necessary to freeze the action. This one's at 1/250th and similar lighting conditions in the same room:
2. A typical test lasted (for us) between 10 to 45 minutes for each belt level. The 70-200mm f/2.8 zoom lens is very heavy; if you want to be handholding that thing for a long time, go for it. A monopod might be better, tripod might be too cumbersome, but check with the instructors about what's permitted. I like to get different angles, and that means moving faster than a tripod will allow. Large pro zoom = big weight, fast prime = less weight.
3. VR gets you nothing in these situations. They are moving quickly, and the extra stop or two (or three or four or whatever) doesn't matter, because those stops are for the lens not moving, not the subject. So if you decide to go with the telephoto, go for the non-VR version (unless you see yourself using the lens for other purposes).
4. That softness when wide open is up to some levels of interpretation, I think. Having said that, I really dig on the 85mm's f/1.8's look at f/2 to f/2.8. But the 70-200mm at f/2.8 can be just gorgeous.
5. Focus is tricky when the focus plane is that thin, and will take practice. It took me a few years to be able to get (what I think are) decent shots of martial arts.
6. Cropping can be tricky. It depends on how far away you are and what kind of shots you want. While I really like the 85mm's look, the 50mm f/1.8 or the 35mm f/1.8 might be better suited for the closeness you have to the action. I'd recommend first using whatever lenses you have and starting to experiment with composition (regardless of whether or not the shots are tack sharp) to determine which focal length you want to start with.
   Good luck!

Answer 2

Try renting the lens you're considering. I think really there isn't any other way to tell if it's going to work. While another answer gives success stories with the 85mm, your access may vary enough to make it the wrong focal length.

Of course, what you really want is the 200mm f/2. It's only $5,000 and you get free shipping!

(Jokes aside, renting that or another exotic lens for special occasions would probably be within your budget. Just be sure to rent it for enough days to get in sufficient practice before you need it.)

Answer 3

Is using a fast prime a workable compromise? Yes, but it is a compromise.

I shoot with Nikkor's 50mm f/1.4 for much of my low light imagery, something I really enjoy shooting. However, for sports I would only use it for features. In other words, for stuff I'm real close to that helps build the story. The obligatory coach-talks-to-team shot or the little brother/sister mimics older brother/sister's sports shot or the guy-wearing-ridiculous-beer-helmet-at-highschool-basketball-game shot.

The reason is this...though f/1.4 can look gorgeous and tremendously increases the amount of light your camera can capture, at 50mm the compression just isn't there. A lens that fast will give you great depth of field, which we all love, but your subjects simply will not pop the way they will with a monster 300mm, 400mm or the often coveted 600mm. You can crop in post all you want, but you won't get that delicious stacked feel you get with long glass.

Another thing to consider is the DOF at f/1.4. When your subjects are moving that fast, especially in figure skating when they are coming or going from the camera quickly, your chance of finding solid focus is minimal. You'll blow most or your shots, and you WILL blow the ones you really want. You will think, "Oh, that's the one! But it's out of focus! Darn!"

The best way to maximize light is to introduce light. May not be possible in these venues to use a strobe. I imagine TKD is not the place to be throwing flashes all over. Figure skating maybe, I would ask. If you want tips on mounting strobes and where to place them, let me know.

One more thing, from your statement, "But if I have to stop it down for sharpness, then I lose shutter speed, or have to bump ISO, which is not going to help get better action shots." This is wrong. You want to bump ISO. You want to be shooting at the fastest possible ISO you can, without sacrificing quality of course. From what I understand the D90 handles ISO fairly well. If you can push it to 1250 or 1600, without insane amounts of noise, you'll be able to shoot with a nice f/5.6 200mm. You'll have your light, you'll have your fast shutter, you'll have workable DOF AND you'll have gorgeous compression.

When I shoot highschool football, I shoot at ISO 1250, underexpose 2/3 stops, deal with any noise in post and have always been happy. I get sharp focus on my subject, I keep motion in the image. The editor is happy. The readers are happy. I'm happy.

All in all you should opt for the telephoto.

Happy Hunting.