Virtually all of the readers of this book will be using zoom lenses rather than fixed focal length lenses. Today, all non-SLR digital cameras are furnished with a zoom lens, and even dSLRs with interchangeable lenses are usually used with a zoom of some type. However, action images are one type of photography that does benefit from the use of specialized lenses, so if you do have a digital SLR you can make the swap. For example, a fixed focal length telephoto with a large maximum aperture can help you shoot in lower light levels. For digital SLR sports photographers, an 85mm f1.8 lens or 400mm f2.8 lens can be a godsend. Fast wide aperture prime lenses can be a lot cheaper than zoom lenses with the same speed, too, because they are simpler to design.
The three things to consider about a lens used for action photography are the focal length, aperture, and whether the camera uses optical or digital magnification.
Focal Length
Your best bet is a camera equipped with a zoom lens that lets you adjust your field of view as the action moves around. I recommend a lens with at least a 3:1 zoom ratio, although the magnification doesn't tell you everything. One 3X zoom might provide the equivalent range of a 32mm to 96mm lens on a film camera, while another 3X zoom might offer the equivalent of 39mm to 117mm. The former would be great for wide-angle sports, but have little in the way of telephoto reach, while the second would provide a little closer view of action that's farther away.
So, in addition to zoom ratio, you should compare the effective focal length of your lens with that of a 35mm camera, because the field of view provided by an actual focal length varies from camera to camera. A true focal length of 25mm may be a telephoto setting on one digital camera, or a wide-angle setting on another, depending on the size of the camera's sensor. (The smaller the sensor, the longer the effective magnification at a particular focal length.)
All digital camera vendors supply this equivalency information. For example, one camera I use has a 7.2 to 50.8mm zoom lens; that provides roughly the same field of view as a 28mm to 200mm zoom lens on a 35mm camera. You can see the difference in viewpoint between a wide-angle lens and a telephoto setting in Figures 5.8 and 5.9.
Figure 5.9. A telephoto lets you zoom in on the action.
For most action photos, the longest zoom setting is more important than the shortest. Few sports require a really wide-angle lens. Most of the time you can't get as close to the action as you'd like. Many benefit from the equivalent of a 135mm to 150mm telephoto optic, particularly if you're unable to patrol the sidelines and must shoot from the stands. Sports like basketball and volleyball do call for shorter focal lengths and wider angles, because you may be literally on top of the action.
Those using some digital SLR cameras can benefit from using lenses designed for 35mm cameras with a sensor that's smaller than the 24mm x 36mm film frame. Mounted on such cameras, the field of view of a lens is cropped, so a 200mm tele actually produces the same field of view as a 320mm long lens (when used with one particular digital camera with a 1.6X "multiplier" factor). Note that some Canon digital cameras (and the now-discontinued Kodak dSLRs) have "full frame" sensors, and don't produce this magnification effect.
You should remember that the crop factor is not true magnification. Your lens still has the same focal length, depth-of-field, and f-stops it would have if used on a full frame camera. That 200mm lens may look as if it were a 320mm optic when you examine the photos, but it's really producing an image that has the edges trimmed off, as shown in Figure 5.10.
Owners of fixed-lens digital cameras aren't left out in the cold when it comes to longer or shorter effective focal lengths. Many models can be fitted with attachments that provide telephoto or wide-angle effects. The best avenue is to choose one of these accessories offered by the manufacturer of your camera; they are designed specifically for your camera's lens and provide the best results. However, third-party vendors also produce generic attachments that can be fitted to a variety of cameras. The cost savings can be significant: a 3X tele converter offered by a major camera manufacturer might cost $250, whereas a generic third-party attachment (possibly with 6X to 8X magnification) can be purchased for $100 or so. The downside? The off-brand accessories might not have the image quality you want.
Your best bet is a camera equipped with a zoom lens that lets you adjust your field of view as the action moves around. I recommend a lens with at least a 3:1 zoom ratio, although the magnification doesn't tell you everything. One 3X zoom might provide the equivalent range of a 32mm to 96mm lens on a film camera, while another 3X zoom might offer the equivalent of 39mm to 117mm. The former would be great for wide-angle sports, but have little in the way of telephoto reach, while the second would provide a little closer view of action that's farther away.
So, in addition to zoom ratio, you should compare the effective focal length of your lens with that of a 35mm camera, because the field of view provided by an actual focal length varies from camera to camera. A true focal length of 25mm may be a telephoto setting on one digital camera, or a wide-angle setting on another, depending on the size of the camera's sensor. (The smaller the sensor, the longer the effective magnification at a particular focal length.)
All digital camera vendors supply this equivalency information. For example, one camera I use has a 7.2 to 50.8mm zoom lens; that provides roughly the same field of view as a 28mm to 200mm zoom lens on a 35mm camera. You can see the difference in viewpoint between a wide-angle lens and a telephoto setting in Figures 5.8 and 5.9.
Figure 5.8. A wide-angle shot shows you the big picture.
Figure 5.9. A telephoto lets you zoom in on the action.
For most action photos, the longest zoom setting is more important than the shortest. Few sports require a really wide-angle lens. Most of the time you can't get as close to the action as you'd like. Many benefit from the equivalent of a 135mm to 150mm telephoto optic, particularly if you're unable to patrol the sidelines and must shoot from the stands. Sports like basketball and volleyball do call for shorter focal lengths and wider angles, because you may be literally on top of the action.
Those using some digital SLR cameras can benefit from using lenses designed for 35mm cameras with a sensor that's smaller than the 24mm x 36mm film frame. Mounted on such cameras, the field of view of a lens is cropped, so a 200mm tele actually produces the same field of view as a 320mm long lens (when used with one particular digital camera with a 1.6X "multiplier" factor). Note that some Canon digital cameras (and the now-discontinued Kodak dSLRs) have "full frame" sensors, and don't produce this magnification effect.
You should remember that the crop factor is not true magnification. Your lens still has the same focal length, depth-of-field, and f-stops it would have if used on a full frame camera. That 200mm lens may look as if it were a 320mm optic when you examine the photos, but it's really producing an image that has the edges trimmed off, as shown in Figure 5.10.
Figure 5.10. Images produced by a lens designed for use with a full-frame camera will be cropped by a digital SLR with a sensor that is smaller than 24 x 36mm.
Owners of fixed-lens digital cameras aren't left out in the cold when it comes to longer or shorter effective focal lengths. Many models can be fitted with attachments that provide telephoto or wide-angle effects. The best avenue is to choose one of these accessories offered by the manufacturer of your camera; they are designed specifically for your camera's lens and provide the best results. However, third-party vendors also produce generic attachments that can be fitted to a variety of cameras. The cost savings can be significant: a 3X tele converter offered by a major camera manufacturer might cost $250, whereas a generic third-party attachment (possibly with 6X to 8X magnification) can be purchased for $100 or so. The downside? The off-brand accessories might not have the image quality you want.
Aperture
The maximum aperture of your lens can be important when shooting action in low-light situations. A "slow" lens can limit the maximum shutter speed you can use, thus affecting your ability to freeze action. For example, if your lens opens no wider than f8 (a common limitation for longer lenses and zoom settings), the best you can do with your camera set to ISO 100 in full daylight is 1/500th second at F8. Your camera may have 1/1000th or briefer setting, but you can't use it without increasing the ISO setting to 200 or higher, thus increasing your chances of detail-robbing noise in your photos. If daylight is waning or you're shooting indoors, an f8 lens may limit you to sluggish 1/250th or 1/125th second speeds.
This is one arena in which digital SLRs shine: They're likely to have lenses available with larger maximum apertures, plus the capability of shooting at ISO settings higher than ISO 400 without appreciable noise. Many dSLRs do a good job at ISO 800-1600 with only minimal noise.
A larger maximum aperture is better, assuming that the lens performs well wide open; an optic that is a bit fuzzy at its maximum aperture is no bargain. Keep in mind that the maximum opening of some zoom lenses varies, depending on the focal length setting. That is, a lens that rates an f4.5 aperture at the 28mm setting may provide only the equivalent of f6.3 or slower when zoomed all the way to the telephoto position.
Lenses that retain the same effective f-stop throughout their zoom range are called constant aperture lenses. If you're considering one for your dSLR, expect to pay more for this feature. For example, Nikon offers a 70mm-300mm f4.5/f5.6 telephoto zoom that can be purchased for less than $150. It also sells another zoom with a more limited 80mm-200mm range, but which has some nice extra features, including internal focusing (the length of the lens doesn't change as you focus), extra-low dispersion glass (which reduces aberrations caused by the lens focusing different colors at slightly different points), and a nifty f2.8 constant aperture. All that stuff is worth a bit more, wouldn't you say? How about $1619?
You might not be willing to pay that much to gain an extra f-stop or two, but pro photographers do it all the time. That's because the use of larger maximum apertures lets you shoot in lower light, and helps in other ways. For example, a large f-stop can improve action photos by isolating your subjects, particularly at longer focal lengths. The reduced depth-of-field afforded by a lens with a wide-open aperture set at the maximum zoom setting can be used creatively, if you're able to focus accurately enough to apply the depth-of-field that remains to the subject. Figure 5.11 shows how reduced depth-of-field can emphasize a subject.
Optical vs. Digital Zoom
I've always maintained that "digital zoom" is a solution in search of a problem. In the quest for longer zoom ratios that can be posted in large letters on the outside of the box, camera manufacturers came up with an amazing and essentially useless feature: the digital zoom. Digital zoom is a way of providing the illusion of a longer focal length lens: Instead of the 135mm equivalent maximum optical setting your camera provides, the field of view can be magically magnified by 2X (or more) giving you an ersatz 270mm lens. Maybe.
Digital zoom doesn't capture anymore information. Instead, it simply fills the photo frame with the pixels captured in the center of the image, using interpolation to enlarge the pixels and provide a magnified image. With some cameras, the results are terrible. You might get better results taking a straight shot and cropping in Photoshop or another image editor, as you can see in Figures 5.12 and 5.13, which show a photo taken with digital zoom and another that's a straight telephoto shot, both captured with the same camera. Other cameras do a fairly good job of interpolation, so the digitally zoomed images are acceptable. I use digital zoom occasionally. Your best bet is not to purchase a camera based on the reach of its digital zoom, and then to test your camera thoroughly to see how well it performs in digital zoom mode before relying on this feature for any important photos.
The maximum aperture of your lens can be important when shooting action in low-light situations. A "slow" lens can limit the maximum shutter speed you can use, thus affecting your ability to freeze action. For example, if your lens opens no wider than f8 (a common limitation for longer lenses and zoom settings), the best you can do with your camera set to ISO 100 in full daylight is 1/500th second at F8. Your camera may have 1/1000th or briefer setting, but you can't use it without increasing the ISO setting to 200 or higher, thus increasing your chances of detail-robbing noise in your photos. If daylight is waning or you're shooting indoors, an f8 lens may limit you to sluggish 1/250th or 1/125th second speeds.
This is one arena in which digital SLRs shine: They're likely to have lenses available with larger maximum apertures, plus the capability of shooting at ISO settings higher than ISO 400 without appreciable noise. Many dSLRs do a good job at ISO 800-1600 with only minimal noise.
A larger maximum aperture is better, assuming that the lens performs well wide open; an optic that is a bit fuzzy at its maximum aperture is no bargain. Keep in mind that the maximum opening of some zoom lenses varies, depending on the focal length setting. That is, a lens that rates an f4.5 aperture at the 28mm setting may provide only the equivalent of f6.3 or slower when zoomed all the way to the telephoto position.
Lenses that retain the same effective f-stop throughout their zoom range are called constant aperture lenses. If you're considering one for your dSLR, expect to pay more for this feature. For example, Nikon offers a 70mm-300mm f4.5/f5.6 telephoto zoom that can be purchased for less than $150. It also sells another zoom with a more limited 80mm-200mm range, but which has some nice extra features, including internal focusing (the length of the lens doesn't change as you focus), extra-low dispersion glass (which reduces aberrations caused by the lens focusing different colors at slightly different points), and a nifty f2.8 constant aperture. All that stuff is worth a bit more, wouldn't you say? How about $1619?
You might not be willing to pay that much to gain an extra f-stop or two, but pro photographers do it all the time. That's because the use of larger maximum apertures lets you shoot in lower light, and helps in other ways. For example, a large f-stop can improve action photos by isolating your subjects, particularly at longer focal lengths. The reduced depth-of-field afforded by a lens with a wide-open aperture set at the maximum zoom setting can be used creatively, if you're able to focus accurately enough to apply the depth-of-field that remains to the subject. Figure 5.11 shows how reduced depth-of-field can emphasize a subject.
Figure 5.11. Use depth-of-field to concentrate attention on a subject.
Optical vs. Digital Zoom
I've always maintained that "digital zoom" is a solution in search of a problem. In the quest for longer zoom ratios that can be posted in large letters on the outside of the box, camera manufacturers came up with an amazing and essentially useless feature: the digital zoom. Digital zoom is a way of providing the illusion of a longer focal length lens: Instead of the 135mm equivalent maximum optical setting your camera provides, the field of view can be magically magnified by 2X (or more) giving you an ersatz 270mm lens. Maybe.
Digital zoom doesn't capture anymore information. Instead, it simply fills the photo frame with the pixels captured in the center of the image, using interpolation to enlarge the pixels and provide a magnified image. With some cameras, the results are terrible. You might get better results taking a straight shot and cropping in Photoshop or another image editor, as you can see in Figures 5.12 and 5.13, which show a photo taken with digital zoom and another that's a straight telephoto shot, both captured with the same camera. Other cameras do a fairly good job of interpolation, so the digitally zoomed images are acceptable. I use digital zoom occasionally. Your best bet is not to purchase a camera based on the reach of its digital zoom, and then to test your camera thoroughly to see how well it performs in digital zoom mode before relying on this feature for any important photos.
Figure 5.12. This photo was taken using digital zoom, and isn't very sharp compared to the next image.
Figure 5.13. This picture was taken with the same camera as a normal telephoto shot, then enlarged.
Digital SLRs generally don't have this feature, because they don't need it; you can simply change your lens for one that's longer. You'll find digital zoom primarily on point-and-shoot and EVF-style cameras.
If you do use digital zoom, learn how it operates with your camera so you can apply it quickly. One way to implement this feature is simply to allow the zoom control to extend past the optical zoom territory into the realm of digital zoom. Usually, a bar showing the zoom level appears on the LCD on the back of the camera, with a marking showing where optical zoom leaves off and digital zoom begins, as in Figure 5.14. Other cameras use a magnification button on the back of the camera. Press it, and the lens zooms in, with either a magnified view in the viewfinder or, perhaps, a cropped image showing how much of the original view is being captured. The magnified view is preferred, because it allows you to evaluate your image at full size.
Figure 5.14. An indicator on LCD shows when you've entered digital zoom territory.
Exposure Controls
Exposure controls help determine whether your image has a pleasing tonal range, and whether there is sufficient detail in both the highlights and shadows. (The quality and quantities of the light are other factors.) Even the best action photograph can be ruined if it's not exposed properly. I'll show you what to look for in exposure controls in this section.
Exposure Modes
Your digital camera probably offers a variety of exposure modes, and might even include one especially for action photography. When choosing an exposure mode, keep in mind the shutter lag problems discussed previously. Here are the most common exposure modes, and how they relate to action pictures.
- Full auto. The least expensive digital cameras might have only a basic full-auto exposure mode, while more advanced models will offer this as an option. In either case, the camera's logic chooses both shutter speed and aperture using simple rules. For example, the camera may shoot at f8 using whatever shutter speed provides the correct exposure until the exposure becomes long enough to encourage hand-held blurring (at, say 1/30th second). Then it will switch to a wider f-stop, as necessary. This is not the best mode for action photography.
- Programmed auto. Most digital cameras have more sophisticated programming that takes into account the shooting environment when deciding exposure settings. For example, if photographs are being taken in dim light, the camera assumes that you're indoors; in bright light, that you're outdoors. Lens openings and shutter speeds are selected based on typical shooting situations in these environments.
- Programmed selective/scene modes. Most digital cameras have selective programs, also called "scene modes" you can choose for automatic exposure under specific conditions. The one you want to opt for is the action/sports setting. In such cases, the camera will try to use the shortest shutter speed possible. It might even automatically boost the ISO rating (if you've set ISO to Auto) or use other tricks to optimize your exposure for fast-moving subjects. If you must use automatic exposure, this is your best choice.
- Aperture priority. In this mode, you set the lens opening, and the camera automatically chooses a shutter speed to suit. Use this if you want to select a specific f-stop, say to increase/decrease depth-of-field. Because aperture priority offers little control over shutter speed, you probably won't use it frequently for sports photos.
- Shutter priority. In this mode, you choose a preferred shutter speed, and the camera selects the lens opening. That lets you select 1/500th or 1/1000th second or shorter to stop action, yet retain the advantages (barring shutter lag) of automatic exposure. This is the mode to use if you're taking photos under rapidly changing light conditions. I use it for outdoor sports on partly cloudy days in which a playing field may alternate between bright sunlight and overcast within the space of a few minutes, depending on how the clouds move. It's also a good choice for photos taken as the sun is setting, because the camera automatically compensates for the decreasing illumination as the sun dips below the horizon.
- Manual exposure. I end up using manual exposure for many of my action photographs. Indoors, the illumination doesn't change much. Most sports arenas, gymnasiums, and other sites have strong overhead illumination that allows taking pictures at 1/250th second at f2.8 using ISO 400 or 800 settings. I might also use flash indoors. Outside, I carefully watch the lighting and change exposure to suit.
Monitoring Exposure
Your camera's built-in light meter might do the job for you, especially if it has a readout that shows exactly how much over- or under-exposure you're working with at any given moment. Unfortunately, a low-end digital camera might be equipped with nothing more than a red LED that blinks when the camera decides there isn't enough light to take a picture. In the worst case, you'll be blocked from actually taking the picture.
Working on the theory that the photographer should know best whether the picture is worth taking or not, I use only cameras that give me the freedom to goof in manual mode, should I want to intentionally take a severely backlit photograph or exercise some other creative license. In manual exposure mode, I sometimes use a handheld light meter and transfer the settings to my digital camera. I tend to use a handheld light meter more than the average amateur photographer, a habit that extends back to my days when people paid me lots of money to know exactly what lighting conditions I was shooting under. You won't find these in use much anymore, because the exposure meters in digital cameras have gotten so good.
Handheld meters are available in several varieties, including "spot" meters that zero in on a specific point you aim them at, and "incident" meters, which measure the light that falls on their sensors (usually a dome shape, like that shown in Figure 5.15). Some are combination meters that offer both modes, and can work with continuous lighting or electronic flash. The disadvantage of the incident meter, of course, is that it only works when the light at the camera position is substantially the same as the light falling on the subject, assuming you don't want to run out onto the field and measure from there.
Better cameras let you choose the area being monitored for correct exposure. For action photography, it's handy to have a spot meter option that's easily accessible. With one of my digital cameras, all I need to do is press the Spot button and hold it down to meter the light at any point I choose.
More sophisticated digital cameras may have various exposure modes, which I explained in some detail in Chapter 2. To recap, you might be able to choose from:
Your camera's built-in light meter might do the job for you, especially if it has a readout that shows exactly how much over- or under-exposure you're working with at any given moment. Unfortunately, a low-end digital camera might be equipped with nothing more than a red LED that blinks when the camera decides there isn't enough light to take a picture. In the worst case, you'll be blocked from actually taking the picture.
Working on the theory that the photographer should know best whether the picture is worth taking or not, I use only cameras that give me the freedom to goof in manual mode, should I want to intentionally take a severely backlit photograph or exercise some other creative license. In manual exposure mode, I sometimes use a handheld light meter and transfer the settings to my digital camera. I tend to use a handheld light meter more than the average amateur photographer, a habit that extends back to my days when people paid me lots of money to know exactly what lighting conditions I was shooting under. You won't find these in use much anymore, because the exposure meters in digital cameras have gotten so good.
Handheld meters are available in several varieties, including "spot" meters that zero in on a specific point you aim them at, and "incident" meters, which measure the light that falls on their sensors (usually a dome shape, like that shown in Figure 5.15). Some are combination meters that offer both modes, and can work with continuous lighting or electronic flash. The disadvantage of the incident meter, of course, is that it only works when the light at the camera position is substantially the same as the light falling on the subject, assuming you don't want to run out onto the field and measure from there.
Figure 5.15. A handheld light meter can come in handy at sports events to confirm the correct exposure.
Better cameras let you choose the area being monitored for correct exposure. For action photography, it's handy to have a spot meter option that's easily accessible. With one of my digital cameras, all I need to do is press the Spot button and hold it down to meter the light at any point I choose.
More sophisticated digital cameras may have various exposure modes, which I explained in some detail in Chapter 2. To recap, you might be able to choose from:
- Evaluative matrix. The camera examines many different points within the scene and chooses an exposure based on what the camera thinks the subject matter consists of. Some digital cameras have more than 1,000 points in the matrix used to evaluate exposure. This is a good choice for action photography of scenes that don't include extra bright or extra dark areas.
- Center weighted. Most of the emphasis is given to the center of the image. If your action will take place mostly in the center of the frame, this mode can work.
- Spot metering. A small center area is used exclusively for calculating exposure. This may be your best choice for night football, beach volleyball, or other sports in which your subjects are likely to be surrounded by dark or light areas.
Focus Controls
Action photography is one field that can benefit from automatic focus, as long as the focus feature operates quickly enough to avoid delaying the exposure. As described in the shutter lag section earlier, many cameras take so long to focus that pictures can be lost while you wait for the camera to zero in on the sharpest point.
For that reason, you'll want to test your camera's automatic focus features carefully in real action photography situations before attempting any crucial work. With players racing around your field of view at a furious pace, the ability to allow your camera to determine the correct focus is a valuable capability. You have enough to think about! Here are the kinds of focus options you may be able to choose from:
All of us photography cognoscenti have smiled at sports events when an amateur photographer high in the stands attempted to snap a flash photograph of the game from 50 yards away. Everyone knows that a point-and-shoot camera's built-in flash produces its best results from no more than 10-12 feet away from the subject. Of course, I never mention this to the hapless amateurs, because they invariably reach into a pocket and pull out an abominable photo (which they nevertheless find perfectly acceptable) taken at the previous game under identical conditions. In virtually all cases, they lucked out and had used a film that was fast enough to produce a picture under the available light, or their digital camera automatically shifted into fuzzy high-ISO mode. The flash had little or nothing to do with the exposure.
Action photography is one field that can benefit from automatic focus, as long as the focus feature operates quickly enough to avoid delaying the exposure. As described in the shutter lag section earlier, many cameras take so long to focus that pictures can be lost while you wait for the camera to zero in on the sharpest point.
For that reason, you'll want to test your camera's automatic focus features carefully in real action photography situations before attempting any crucial work. With players racing around your field of view at a furious pace, the ability to allow your camera to determine the correct focus is a valuable capability. You have enough to think about! Here are the kinds of focus options you may be able to choose from:
- Continuous autofocus. As you'd expect from its name, continuous autofocus sets your camera to adjust focus all the time once you partially depress the shutter release. That's great for fast-moving subjects, because an object moving quickly towards you or away from you can change its plane of focus rapidly in a few seconds. Some cameras include predictive autofocus, in which the camera estimates where the subject will be when you do press the shutter release all the way, in effect focusing ahead of the actual movement. The main problem with continuous autofocus is that you may end up with an out-of-focus picture if your subject is moving too fast for the camera's autofocus system to keep up.
- Single autofocus. This mode sets focus once, locking it in until the shutter release is pressed all the way, or you take your finger off the button. Single autofocus reduces your chances of getting an out-of-focus picture; in fact, your camera may prevent you from taking a picture at all while it is seeking the correct focus point. This is not your best choice for action photography, because you'll sometimes prefer a slightly out-of-focus image taken right now versus a sharply focused image captured whenever the camera got around to deciding what the best focus point was.
- Dynamic focus area. Because your dSLR has more than one focus sensor checking your frame, it may shift among them as focus is calculated. With dynamic area autofocus, the camera may automatically switch from using one sensor to a different sensor if it detects subject motion. In a mode called closest subject, this dynamic mode may be selected based on what subject is nearest to the camera. Dynamic focus area is good for action photography if your subject is likely to be either the closest object to the camera or a subject that the camera is likely to zero in on.
- User selected focus area. You switch from one focus area to another using the cursor pad, as shown in Figure 5.16. Autofocus systems frequently use the same general zones applied by the autoexposure system, and use a single on-screen set of indicators to show them. The focus area in use will often be indicated by a glowing red light, as you can see in the figure.
Figure 5.16. When you switch from one autofocus zone to another, the focus priority area will often be indicated with a green or red glow.
- Focus override. Cameras and lenses may have an AF/M button you can use to switch between autofocus and manual. Some let you use a mode that focuses automatically, but which can be fine-tuned manually with no danger of grinding gears or gnashing teeth.
- Macro lock/lockout. Some cameras and lenses have a provision for locking out the closest or most distant focus areas, so that focus can be achieved only within a narrower range. That can come in handy when you're shooting sports, because the lens won't bother seeking close focus, which can be time-consuming.
- Autofocus assist lamp. This is an optional feature that can improve autofocus operation in low light situations. The light, which is most often either white or red, is rarely strong enough to be of much help beyond a few feet, tends to be annoying to your human or animal subjects, and uses enough power to drain your battery a bit. You'll probably want to turn this off when shooting action.
- For reducing shutter lag. Avoid automatic focus if it introduces massive shutter lag problems to your action photography experience. Use manual focus instead.
- To use auto prefocus. Use automatic focus if you're able to prefocus on a specific point by partially depressing the shutter button. If your camera allows you to lock in focus, and then take a photograph quickly by depressing the shutter button the rest of the way, autofocus may work for you.
- When grabbing very fast action. Experiment with automatic focus if the action changes quickly from one point to another. You may not be able to focus manually fast enough. I've lost as many pictures to poor focus as I have to shutter lag.
- To capture predictable action. Manual focus is a good choice when you know in advance where the action will be taking place (for example, around the hoop at a basketball game) and can help your camera operate more quickly than in autofocus mode.
- To maximize limited opportunities. Manual focus works when your shooting is limited by other factors. At baseball games, for example, if I'm working with a camera with a limited zoom range, I find that from my usual position by the first base dugout my only realistic subjects are the batter, pitcher, and first base positions. I can prefocus on one of those spots and be ready for action at that position.
- When there are depth-of-field considerations. Manual focus is best when you need to control your depth-of-field. For example, you might want to shoot a photo of spectators watching a game. In that case, you wouldn't mind if the game itself is a little out-of-focus. Your digital camera's autofocus might focus on the playing field in the center of the image rather than the spectators at the edges of the frame.
- When there's enough time to focus. Manual focus is practical only when you're able to accurately set focus manually. Distance guesstimates work sometimes. I use this method at football games, where I can use the yardline markers as a gauge, and at baseball games, because the distance between bases, or from home plate to the pitcher's mound is a standard increment. If you're focusing using your camera's viewfinder, remember that some viewfinders display sharp focus better than others, and that your ability to focus visually may suffer when the illumination wanes.
All of us photography cognoscenti have smiled at sports events when an amateur photographer high in the stands attempted to snap a flash photograph of the game from 50 yards away. Everyone knows that a point-and-shoot camera's built-in flash produces its best results from no more than 10-12 feet away from the subject. Of course, I never mention this to the hapless amateurs, because they invariably reach into a pocket and pull out an abominable photo (which they nevertheless find perfectly acceptable) taken at the previous game under identical conditions. In virtually all cases, they lucked out and had used a film that was fast enough to produce a picture under the available light, or their digital camera automatically shifted into fuzzy high-ISO mode. The flash had little or nothing to do with the exposure.
Pros and Cons
Even so, we big-time photographers who understand electronic flash find some use for it, because there are advantages as well as disadvantages to sports flash photography. The advantages are well-known:
Even so, we big-time photographers who understand electronic flash find some use for it, because there are advantages as well as disadvantages to sports flash photography. The advantages are well-known:
- The brief duration of electronic flash can often freeze fast action even more effectively than your camera's shortest shutter speed.
- Electronic flash can provide enough light to illuminate sports venues that are far too dim for good available light photographs.
- Electronic flash works just fine in close confines, so it works indoors for basketball photos, or outdoors for football pictures taken close to the sidelines.
- Flash pictures often look like flash pictures, with very bright foregrounds and pitch-black backgrounds. For a horrid example of this, I've resurrected my very first published photo, dating back to my film days, as shown in Figure 5.17. It's an example of the traditional "basketball instead of a head" shot that every sports photographer strives for, made to seem as if it were taken outdoors at night thanks to the overpowering glare of an electronic flash. Such photos can look dated (and this one is dated), because many sports pictures taken today in venues that are better lit, with faster films and faster digital sensors have no such look. Or, you can use the effect artistically to isolate your main subjects from the rest of the playing field.
Figure 5.17. You can never mistake a sports photo taken with flash for an existing light picture.
- Electronic flash can produce a "ghosting" effect, which occurs when the main exposure is made by the flash, and a secondary, blurry exposure is produced when the available light is strong enough. Some cameras won't synchronize with the electronic flash at particular shutter speeds, particularly if your digital camera uses a mechanical shutter. Because the electronic flash exposure is over in as little as 1/50,000th of a second, the flash needs to be triggered at a point when the entire sensor is exposed to the light. For some cameras, that happens only when shutter speeds of 1/125th of a second or slower are used. For faster shutter speeds, a smaller opening is passed vertically or horizontally in front of the sensor, and only the portion exposed when the flash is triggered will show up in your photo. The slower the shutter speed you must use to synch with your flash, the more likely you're to get ghosting effects. Figure 5.18 shows a typical image with ghosting problems.
Figure 5.18. This picture is actually two exposures: one made by flash and one, a ghost image, that resulted from the existing light.
- Some venues won't let you use flash. I've never had a problem at the high school, college, or pro levels, but have been chastised sharply by the refs when attempting to use flash at middle school basketball games. Although personally I feel that these young stars need to get used to playing under the glare of electronic flash illumination, I always abide by the officials' rulings.
- Electronic flash eats up your camera's internal batteries quickly, and drains the cells in an external flash unit almost as quickly. I recently photographed a football game and took along six sets of 2000 mAh Nickel Metal Hydride batteries for my camera and external flash unit. By the end of the game I had a few hundred exposures and six sets of dead batteries.
Flash Sync and You
Your digital camera probably has several flash synchronization settings that can help you work with the ghosting effect, either to reduce it or enhance it. Ghosting is such a common occurrence that photographers can even use it as a special effect, producing a photo that combines a sharp photo with a trailing blurry ghost that follows behind. All you need to do is use flash at an f-stop and shutter speed that will also allow a conventional image.
Unfortunately, your digital camera may work against you. That happens when the flash is triggered at the end of the exposure rather than at the beginning of it. You'll end up with a ghost image preceding the subject, followed by a sharp flash image at the end of the exposure, when you want the reverse. Your digital camera may have a setting to let it control exactly when the flash is fired. Set properly, the flash will fire immediately, but your electronic/mechanical shutter will remain open long enough to produce the ghost image as the main subject continues on its path.
Here are the most common synchronization options found on digital cameras:
Your digital camera probably has several flash synchronization settings that can help you work with the ghosting effect, either to reduce it or enhance it. Ghosting is such a common occurrence that photographers can even use it as a special effect, producing a photo that combines a sharp photo with a trailing blurry ghost that follows behind. All you need to do is use flash at an f-stop and shutter speed that will also allow a conventional image.
Unfortunately, your digital camera may work against you. That happens when the flash is triggered at the end of the exposure rather than at the beginning of it. You'll end up with a ghost image preceding the subject, followed by a sharp flash image at the end of the exposure, when you want the reverse. Your digital camera may have a setting to let it control exactly when the flash is fired. Set properly, the flash will fire immediately, but your electronic/mechanical shutter will remain open long enough to produce the ghost image as the main subject continues on its path.
Here are the most common synchronization options found on digital cameras:
- Front-sync. In this mode, the flash fires at the beginning of the exposure. If the exposure is long enough to allow an image to register by existing light as well as the flash, and if your subject is moving, you'll end up with a streak that's in front of the subject, as if the subject were preceded by a ghost. Usually, that's an undesirable effect.
- Rear-sync. In this mode, the flash doesn't fire until the end of the exposure, so the ghost image is registered first, and terminates with a sharp image at your subject's end position, with the well-known streak (like that which followed The Flash everywhere) trailing behind. That can be a bad thing or a good thing, depending on whether you want the ghost image.
- Slow-sync. This mode sets your camera to use a slow shutter speed automatically, to record background detail that the flash, used to expose a subject closer to the camera, fails to illuminate. This mode can improve your flash images if you hold the camera steady and the subject is not moving. So, slow-sync is best reserved for non-sports images, or photographs in which the subject is approaching the camera. Otherwise, you can almost guarantee ghost images.
Compatibility
If you're using flash, consider working with a more powerful external flash unit that's compatible with your digital camera. Such a flash may not be easy to find. Some digital cameras are able to use only dedicated flash units made specifically for them. One reason for that is often that the triggering voltage of the vendor's own flash units is low, and electronic flash that use higher voltages may fry the electronics. Another reason is that only a dedicated flash unit might be compatible with the flash autoexposure mechanism of your camera. Unless you want to set flash exposure manually, you'll be better off with the recommended units.
One of my favorite non-SLR digital cameras has a standard PC sync connector that's compatible with any electronic flash I care to use. It works happily with my studio flash units, and is equally at home with the "potato masher" flashgun I use at night football and soccer games when the field lighting isn't strong enough.
Don't bother with multiple flash units for sports. They're best suited for portraiture and other lighting-intensive photo arenas. Pros relied on multiple flash units extensively before the fast color films and more sensitive digital cameras of today became prevalent. I used to watch these folks spend hours suspending their radio-controlled strobes from the rafters of sports arenas before an important event. Is all that work worth it just to make the cover of Sports Illustrated? You should be able to get by with a single flash unit or no flash at all.
If you're using flash, consider working with a more powerful external flash unit that's compatible with your digital camera. Such a flash may not be easy to find. Some digital cameras are able to use only dedicated flash units made specifically for them. One reason for that is often that the triggering voltage of the vendor's own flash units is low, and electronic flash that use higher voltages may fry the electronics. Another reason is that only a dedicated flash unit might be compatible with the flash autoexposure mechanism of your camera. Unless you want to set flash exposure manually, you'll be better off with the recommended units.
One of my favorite non-SLR digital cameras has a standard PC sync connector that's compatible with any electronic flash I care to use. It works happily with my studio flash units, and is equally at home with the "potato masher" flashgun I use at night football and soccer games when the field lighting isn't strong enough.
Don't bother with multiple flash units for sports. They're best suited for portraiture and other lighting-intensive photo arenas. Pros relied on multiple flash units extensively before the fast color films and more sensitive digital cameras of today became prevalent. I used to watch these folks spend hours suspending their radio-controlled strobes from the rafters of sports arenas before an important event. Is all that work worth it just to make the cover of Sports Illustrated? You should be able to get by with a single flash unit or no flash at all.
Flash Exposure
Learn to use your digital camera's various flash exposure modes. You can usually control how the flash fires, as well as the system used to measure the exposure. The most common exposure modes are these:
Learn to use your digital camera's various flash exposure modes. You can usually control how the flash fires, as well as the system used to measure the exposure. The most common exposure modes are these:
- TTL (through-the-lens) metering. With this type of exposure, the camera measures the flash illumination that reaches the sensor and adjusts the exposure to suit. If you're photographing a subject that reflects or absorbs a lot of light, the exposure setting may not be accurate. Some camera/flash tandems use complex communication systems to convey information back and forth with imperceptible pre-flashes. The camera tells the flash unit when to fire and, perhaps, what zoom setting is being used with the camera's lens. The flash takes that information into account, and may respond by telling the camera the exact color temperature that will be used during the ensuing exposure.
- Pre-flash metering. The camera fires a pre-flash and uses that information only to calculate exposure. This is the best mode to use when your exposure is "non-standard" in some way, as when you put a diffuser on the flash, a darkening filter on your lens, or use an external flash unit.
- Integrated metering. The camera triggers a pre-flash just before the exposure, measures the light that reflects back, and then integrates that information with distance data supplied by your camera's focus mechanism. The camera knows roughly how far away the subject is and how much light it reflects, and can calculate a more accurate exposure from that.
- Manual control. In this mode, the flash fires at whatever power setting you specify for the flash (full power, half power, and so forth) and you calculate the exposure yourself, using a flash meter or various formulas using guide numbers (values that can be used to calculate exposure by dividing them by the distance to the subject).
- Electronic flash units have firing modes, too, in addition to exposure modes. The most common modes you'll encounter are these (not all are available with every digital camera):
- Always flash. Any time you flip up the electronic flash on your camera, or connect an external flash, the flash will fire as the exposure is made.
- Autoflash. The flash fires only when there isn't enough light for an exposure by available light.
- Fill flash/forced on. The flash fires in low light levels to provide the main source of illumination, and in brighter conditions such as full sunlight or backlighting, to fill in dark shadows.
- Red-eye flash. A pre-flash fires before the main flash, contracting the pupils of your human or animal subjects, and reducing the chance of red-eye effects, while annoying your victim.
- Rear sync. Controls whether the flash fires at the beginning or end of an exposure.
- Wireless/remote sync. In this mode, the camera triggers an external flash unit using a wireless sync unit. As with all such remote controls, a selection of perhaps four or more channels are available so you can choose one that's not in use by another nearby photographer who also happens to be using wireless control. Unless you're covering a major event, you probably won't experience many conflicts when using wireless control. Some remote control/slave flash setups trigger by optical means: The camera's flash is detected and sets off the remote flash. You may be able to set the camera flash to low power so the main illumination comes from the remote.
Tripods and Monopods for Action
A tripod, or its single-legged counterpart the monopod, supports your camera during exposures, providing a steadying influence that is most apparent when shooting with long lenses or slow shutter speeds. By steadying the camera, a tripod/monopod reduces the camera shake that can contribute to blurry photos.
I'd never use a tripod at all at any event at which I needed to move my shooting position frequently. Tripods take up too much space and are clumsy to move about. To use one along the sidelines of any field game would be insane, probably prohibited, and sure to incur the derision of your would-be colleagues. A tripod is most useful when the camera must remain absolutely steady, such as for an exposure of more than 1/15th second. A monopod doesn't provide quite as much support, but is sufficient for action photography. I saw plenty of monopods at the last football game I covered, and more than a few chestpods, which brace against your chest to steady the camera.
A monopod, like the one shown in Figure 5.19, sharply reduces camera shake, which can be obvious even at shutter speeds as fast as 1/125th second (or even faster). A longer lens may be physically large enough to cause some camera shake of its own, and even a modestly sized tele on a digital camera magnifies any camera shake enough to provide more blurring than the movement of your subjects.
Tripods are most useful for sports like baseball, where the action happens in some predictable places, and you're not forced to run around to chase it down.
If you think your hands are steady enough at faster shutter speeds, you might want to conduct a simple test. You'll probably be surprised to discover that camera shake might be noticeable at fairly brief shutter speeds. Even veteran photographers who pride themselves at being able to squeeze off sharp photos at 1/30th or 1/15th second are surprised at the results of this test.
Although there are several ways to conduct the test, my favorite is to use a large piece of aluminum foil, mounted vertically at eye-level and backlit. Poke some tiny holes in the aluminum foil so that little pin-pricks of light are visible from the back illumination.
Then, position yourself 10 to 20 feet from the foil, rack your zoom lens out to its maximum magnification, and fire off some shots at various shutter speeds. You might have to use your camera's manual exposure or shutter preferred modes to select the speeds. For best results, focus carefully on the foil. Then dump all the images from your camera to your computer and view them in your image editor. If your hand is steady, each pin-prick will appear to be round and sharp in the image. As you reduce the shutter speed, you'll probably notice that the pin circles become elongated in the vertical, horizontal, or diagonal directions, depending on the bias of your shakiness. At worst, you may notice little wavering trails of light that show you're not merely shaking a bit, but positively quivering, as you can see in Figure 5.20.
After you've reviewed the results, either practice hand-holding your camera more steadily, switch to a higher shutter speed, or get yourself a tripod/monopod camera support.
Your Digital Film
I covered most of what you need to know about digital film in Chapter 2, but the topic deserves a revisit, because action photography poses some special demands. There are two key things about this kind of picture taking that affects your choice of memory card:
A tripod, or its single-legged counterpart the monopod, supports your camera during exposures, providing a steadying influence that is most apparent when shooting with long lenses or slow shutter speeds. By steadying the camera, a tripod/monopod reduces the camera shake that can contribute to blurry photos.
I'd never use a tripod at all at any event at which I needed to move my shooting position frequently. Tripods take up too much space and are clumsy to move about. To use one along the sidelines of any field game would be insane, probably prohibited, and sure to incur the derision of your would-be colleagues. A tripod is most useful when the camera must remain absolutely steady, such as for an exposure of more than 1/15th second. A monopod doesn't provide quite as much support, but is sufficient for action photography. I saw plenty of monopods at the last football game I covered, and more than a few chestpods, which brace against your chest to steady the camera.
A monopod, like the one shown in Figure 5.19, sharply reduces camera shake, which can be obvious even at shutter speeds as fast as 1/125th second (or even faster). A longer lens may be physically large enough to cause some camera shake of its own, and even a modestly sized tele on a digital camera magnifies any camera shake enough to provide more blurring than the movement of your subjects.
Figure 5.19. You can fasten the monopod to the tripod socket of your camera, or mount it directly to a longer lens that includes its own tripod socket collar.
Tripods are most useful for sports like baseball, where the action happens in some predictable places, and you're not forced to run around to chase it down.
If you think your hands are steady enough at faster shutter speeds, you might want to conduct a simple test. You'll probably be surprised to discover that camera shake might be noticeable at fairly brief shutter speeds. Even veteran photographers who pride themselves at being able to squeeze off sharp photos at 1/30th or 1/15th second are surprised at the results of this test.
Although there are several ways to conduct the test, my favorite is to use a large piece of aluminum foil, mounted vertically at eye-level and backlit. Poke some tiny holes in the aluminum foil so that little pin-pricks of light are visible from the back illumination.
Then, position yourself 10 to 20 feet from the foil, rack your zoom lens out to its maximum magnification, and fire off some shots at various shutter speeds. You might have to use your camera's manual exposure or shutter preferred modes to select the speeds. For best results, focus carefully on the foil. Then dump all the images from your camera to your computer and view them in your image editor. If your hand is steady, each pin-prick will appear to be round and sharp in the image. As you reduce the shutter speed, you'll probably notice that the pin circles become elongated in the vertical, horizontal, or diagonal directions, depending on the bias of your shakiness. At worst, you may notice little wavering trails of light that show you're not merely shaking a bit, but positively quivering, as you can see in Figure 5.20.
Figure 5.20. Backlit test pattern photographed at 1/1000th second (upper left); 1/30th second (upper right); 1/4 second (lower left); and 1 second (lower right).
After you've reviewed the results, either practice hand-holding your camera more steadily, switch to a higher shutter speed, or get yourself a tripod/monopod camera support.
Your Digital Film
I covered most of what you need to know about digital film in Chapter 2, but the topic deserves a revisit, because action photography poses some special demands. There are two key things about this kind of picture taking that affects your choice of memory card:
- You'll probably be using your digital camera's burst mode, or "motor drive" capabilities more heavily when shooting action pictures. Even a short sequence can eat up six or eight exposures. At that rate, you can run through your average digital film card in a few minutes. You'll need lots of film cards.
- Even if you're firing off single frames, it's common to take one picture after another. As I mentioned before, the number of sequential photos you can take is limited both by the amount of internal RAM your digital camera has, as well as how quickly it can be offloaded to your film card. In practice, the transfer speed of a digital memory card rarely makes much difference, but action photography is one of those exceptions. You don't want to wait for endless seconds as your previous pictures are transferred, particularly when new action is unfolding in front of you. If you do a great deal of action photography, you'll want to find and purchase memory cards with the fastest transfer speeds. Speeds can range from 1MB to 20MB per second (depending on how the manufacturer measures transfer speed) or even much higher.
- When I photographed a professional baseball game last summer, I took along both a Kodak 14-megapixel pro camera, as well as a more consumer-oriented 5MP Minolta model. The Kodak camera had a 1GB Hitachi/IBM mini hard disk, and the Minolta was outfitted with an array of CompactFlash cards in sizes from 64 to 256MB. I barely made it through the game! If you can't afford to buy more memory cards than you possibly can use, here are some tips for stretching your available removable storage as far as it will go.
- Choose compact file formats. I routinely use either my digital camera's RAW format, or the high-resolution TIFF format for everyday photography, because storage space isn't an issue and maximum sharpness is. As you learned in Chapter 4, modest JPEG compression can squeeze down photos to a fraction of their TIFF equivalents without really costing you too much in sharpness. Use JPEG when you can, and select a compression/quality ratio that's compatible with your image quality expectations.
- Reduce your resolution. Do you really need to shoot at 4500 x 3000 pixels? Switch to a lower resolution and you can store many times more images in the same storage space. Perhaps the solution is as simple as moving closer so the full image can be used instead of a cropped version of a higher resolution version. Some digital cameras automatically switch to a lower resolution mode anyway when you're using high-speed sequence modes.
- Use sequence mode only when you really feel you need to, and reduce the number of in-between photos that you didn't really want.
- Review your shots after taking them (you'll want to do that to correct your mistakes on future shots, anyway) and press the Quick Erase button to remove the real dogs. Even if you're an above-average shooter, you might discover that half your original photos are clunkers that don't deserve to be saved, anyway. Deleting them now saves space on your film card for better photos later.
- Investigate carrying along one of those portable hard drives that can transfer your pictures from the film card, freeing the space on the card. What else do you have to do during halftime? There's an adapter for the Apple iPod that lets you transfer pictures from a memory card onto the iPod's hard disk.
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