[Disclaimer: I'm well aware that this article assumes some familiarity with basic exposure concepts which some people may not have. I'm sorry, but I had to stay on topic for a post that was already getting pretty long. The explanation of those concepts must be saved for another day. Until I write my own versions, Google is your friend. Speaking of the length, if you just want a quick hit list without the full story, skip to the end.]
Don't bother trying to stop action with a camera phone. Auto settings: ISO 160, 1/15s, f/2.6, no flash |
First, it's hard for cameras to quickly lock in focus. Consumer-grade hardware, in particular, is often happy to hunt back and force through its entire focus range because it can't see well enough to make out the high-contrast edges that distinguish "in focus" from "out of focus." Wider apertures help this situation by allowing more light into the camera. A pro with a decent budget would be using an f/2.8 lens to shoot sports in order to give the camera as much light as possible for focusing. An avid hobbyist might use an f/4 lens, which passes half as much light. Most consumer-grade lenses can only manage f/5.6 at the long end of their zoom, and that teeters on the boundary of how much light a camera needs in order to focus. Such cameras will have trouble focusing quickly on moving subjects, and may not focus accurately when they do stop hunting.
From a different game: ISO 6400, 1/180s, f/4, no flash. Note the blurred feet and the heavy noise that kills sharp details. Click the following image to see a 100% crop. |
While consumer-grade lenses typically only have apertures of f/5.6 at the long end, more expensive lenses can frequently reach f/2.8. The aperture refers to the size of the opening in your lens through which light passes. The smaller the number, the bigger the hole and the more light makes it through. An f/2.8 lens will allow you to use a shutter speed four times faster than will an f/5.6 lens, or it will allow an ISO one fourth as high, or some combination of the two. F/2.8 lenses aren't cheap, though. How badly do you want to get that great shot of junior's game-winning layup?
ISO 6400, f/5.6, 1/90s, no flash In Av mode, the dark background tricked the camera into overexposing and using an even slower shutter speed. |
If your lens has a variable aperture (as most inexpensive lenses do), you'll be able to use a wider aperture for wide angle shots (say f/4) than you would for long, telephoto shots (say f/5.6). Use this to your advantage to get the fastest shutter speed possible. Set your camera to aperture priority ("Av" in Canon's user interface), zoom your lens to the widest setting, and set your aperture to its widest setting. Your camera will now automatically choose the shutter speed it thinks is best at whatever aperture your lens is able to provide, given your current focal length. Light-colored walls may throw off the exposure somewhat, but it's better than dealing with unnecessarily slow shutter speeds.
Previously, I've tried shooting most of these games using only ambient room light at ISO 6400 in aperture priority mode at the widest available aperture. See the pair of yellowish images above for one of the best shots I managed in those conditions. The results are OK, but not great. Most are a lot blurrier than this image. Faces lose lots of detail at that ISO, but lower ISO's lose detail to motion blur. It's a catch 22.
Adding flash to the mix
For the final three-game tournament, I decided to use an on-camera flash. Not only does a flash add more light to your subject, which allows the use of a lower ISO, but the flash's pulse is considerably faster than your camera's shutter speed, which helps immensely when it comes to freezing action. You probably can't get away with using a flash from courtside to shoot an NBA game, but the officials aren't nearly so picky at elementary-aged YMCA games. The only trouble I've had with a ref resulted in me having to move from the baseline off toward one corner of the court so that diving players wouldn't get hurt (these gyms sometimes only have a couple feet between the baseline and the concrete wall). I wasn't even using a flash at the time.
70mm, f/4, 1/180s, ISO 1600, toughgreen gel + FL white balance |
Speaking of ghosting, if your flash allows it, you should set it to "second curtain sync" so that it fires at the end of your exposure rather than at the beginning of it. Combining flash with ambient will always create a frozen image with a blur following the path of a moving object. Normally, the blur comes after the flash, which makes the object appear to be moving backward. Second curtain sync makes the blur come first, so the objects appear to be moving the proper direction.
ISO 2500, 1/250s, f/4, flash. Less noise & sharper edges, but note the ambient blur above his hand. Click for a 100% crop. |
The solution to this is to place a "gel" (a colored sheet of plastic) over your flash to match the color of the room lights, then tell your camera to expect everything will match that same color. This enables the entire image (both foreground and background) to be lit by the same color of light, producing a consistent image. Auto white balance probably won't work here, since your camera knows there's a flash being used and would therefore prefer to use a daylight white balance. The trick is figuring out exactly what color the room lights are and then finding a gel (or combination of gels) to match.
The gyms I've been in are usually either fluorescent or something resembling mercury-vapor. Once upon a time, fluorescent tubes meant you could slap a "tough green" filter on your flash and be good to go. With all the different shades of fluorescents these days, that's no longer the case. I find myself needing a half green and a quarter green gel more often than the full toughgreen gel, because today's fluorescent lights just don't have as much of a green cast as they used to. With these gels, the camera's built-in fluorescent white balance setting probably won't cut it, so you'll need to find a white object, photograph it with your lights, and set your camera to a custom white balance matching that test image.
70mm, f/4, 1/180s, ISO 2500, 1/2 CTO gel + 4000K white balance |
They key is to bring a selection of gels and then experiment with the lights when you first arrive in the gym. Set the camera to daylight WB and shoot a test shot with just ambient room light. Is it green? Yellow? Orange? Find a camera WB setting that makes the room colors look natural. Try not to use a custom WB image unless it's your last resort, because it'll be hard to match that with a gel.
Once your ambient light is dialed in, find a flash gel--or a combination of multiple gels--that will produce that same color of light from your flash. Tape the gel(s) over your flash, and you're good to go. This process will take a few minutes, so don't show up right at tip-off and expect to get great shots right away.
If you have a pair of studio lights and a white gym ceiling at your disposal (neither of which I did), you could simply bounce a pair of big, high-power lights off the ceiling to light the entire gym. It works just like my standard party lighting setup, but on a larger scale. It'll provide much more even, pleasing light than will direct, on-camera flash. However, the lights will take on the color cast of the ceiling, and you'll burn some serious juice throwing that much light that far for a couple hundred shots. 110V wall plugs are a must. I've seen this done at a local high school gym with great results.
By the way, this same process works equally well at school programs that take place in these same gyms. The kids are moving a lot slower, but the rooms are also a lot darker, so the same theories apply. At least you can use a tripod for those music programs without sacrificing much to motion blur.
Real world examples
OK, so enough theory. I want to lay out how my setup progressed through each of the games, including what failed, what succeeded, and what changed.
70mm, f/4, 1/250s, ISO 2000, toughgreen gel + FL white balance |
My equipment was my Canon 7D body, my Sigma 17-70mm f/2.8-4.0 lens, and my old-school, manual, Sunpak 544 "potato masher" flash. I set the camera at ISO 1600, the lens at f/4, and the shutter speed waffled between 1/180s and 1/250s. I chose that manual flash because it's the big dog in my bag. I knew it would have the power to reach the other end of the gym without batting an eye. The down side is that I had to set the flash power manually, so I used 1/8 power for shots at the far end of the court & 1/16 power for the near end of the court. I was sitting at one corner of the court and tuned my flash for action in the paint, so my 1/16 flash power tended to really nuke the players if I shot them right in front of my seat. Pity. I lost a couple good action shots to that.
Players too close = too much flash |
The 17-70mm lens was a great range for shooting anything on the near end of the court while seated at one corner. For action at the far end, 70mm limited me to "landscape" shots that showed the entire playing field.
The high-speed focusing motor on that lens (Canon's "USM" or Sigma's "HSM") makes a world of difference when following fast-moving players. I set my focus mode to "AF-SERVO," which tells the camera to continually track focus rather than setting it once and the waiting for the next shot. As long as you keep your subject under your desired focusing point, the camera will keep your subject in focus as they run around the court. My 7D body has 19 focusing points (vs 9 for the lower end bodies), and it allows me to group together 5 or 9 of them to create a larger focus target without having to use all 19 of them. I find that this works better than using just the single center point, which is what I normally do. If you accidentally slip your focus point off the player and onto the background wall, guess what will be in focus when you click the shutter?
Despite the color cast, this game actually yielded the highest percentage of "keeper" shots of the three games I shot that weekend. They did require a bit of postprocessing, though, and the background still had an ugly magenta tint.
Bare flash + daylight white balance (compare below) |
There were no windows in this gym, and the overheads were something other than fluorescent. They cast a light that was quite yellow (a look which was probably accentuated by the floor and wall color). Since the first game left me dealing with fluorescents, I was in that mindset when I first arrived. These lights were definitely not fluorescent, so I shot with a daylight WB and no flash gel through the first half. The resulting shots show good-looking players on a yellowish background. I couldn't even do much about the background in post, which sucked.
1/2 CTO gel + 4000K white balance (compare above) |
I made a couple other changes for this second game that didn't work out so well. First, I opened up the aperture on my lens to its widest setting, which is f/2.8 at the wide end and f/4 at the long end. The problem is that my ISO and shutter speed were set to match f/4, so my background tended to be overly bright in the wide angle shots. I should have forced the lens to f/4 all the time for a consistent background exposure.
Second, because this gym was much larger than the first, I had plenty of room to roam both baselines. I chose to stay in the middle half of the baseline at whichever end of the court my team was shooting toward (I switched ends at half time). Alas, I found that this position created lots more obstructions for me, often in the form of a referee doing his job (not mine) or another low post player blocking my view of a point guard. I got the smallest percentage of keeper shots at this game. Perhaps that was due to the coach's game plan rather than my location, but I can't be sure.
The gear I brought to shoot the 3rd game |
The "near action" rig was the same one I used in the second game. This time, I fixed the settings for both cameras at f/4, 1/250s, ISO 2500 rather than letting the aperture float to f/2.8 for wide shots. The lighting was the same 4000K, 1/2 CTO setting that I finished with at the second gym.
58mm (AF), f/4, 1/250s, ISO 2500, 4000K WB, 1/2 CTO gel on flash. Blueish windows would suck on a sunny day! |
All told, I think I brought a little under $3000 worth of gear to shoot a 6th grade YMCA basketball game. Overkill? Maybe, but that stuff doesn't do me any good sitting at home on the shelf. Besides, the practice never hurts.
200mm (manual focus), f/4, 1/250s, ISO 2500, 4000K WB, 1/2 CTO gel on flash |
Being able to shoot at both ends of the court certainly kept me busy, and I took twice as many photos as I had in each of the previous games (500 for the weekend). Wrangling these two cameras was no picnic. I certainly couldn't keep both around my neck. I ended up hanging the 7D around my neck and laying the 50D down in my open camera bag on the floor next to me when I wasn't shooting with it.
Epilogue
Celebrating a 2-point victory |
- Sit at one corner of the court, as it provides the best vantage points.
- Two camera bodies: one with a 17-70mm lens for close action and one with a 70-200mm lens for distant action.
- Use flashes on both cameras.
- Set the camera white balance to match the gym light, and gel the flash to match that.
- Set the cameras to the max sync speed (often 1/250s), the widest aperture (f/4, in my case), and an ISO that puts the room about one stop darker than it should be.
Hopefully this will help some of you "basketball moms/dads" get some better scrapbook material the next time your youngling has a game. I can't wait for soccer season to start: outdoor sports at mid-day will be a cake walk compared to this.
As always, if you've got more questions or something you'd like to share, please speak up in the comments below. I always love to hear from my readers.
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