First and foremost, gear is not the be all and end all. Creativity will bring the most out of the simplest of gear. We stand on the shoulders of giants now. Remember that it was only a few years ago that high ISOs were all but unusable and that once you'd shot a black and white frame, it stayed black and white. The fact remains, though, that understanding what your gear is capable of is the key to exploiting its strengths and weaknesses, which is where creativity lives. Learning a few simple things about what your existing gear is capable of will do more for your images than any shiny new purchase. Use these five simple exercises to learn more about what the tools you have can do.
Shutter speed is one of the simpler creative controls you have. You can use slower speeds to allow objects in your frame to move, or faster speeds to freeze them in time. Knowing just how much blur will be created or how fast your shutter needs to be to stop motion is key to using it creatively.
Objects moving perpendicular to your lens will require significantly shorter shutter speeds than those moving toward or away from it. For example, if a person is walking across your frame at a normal pace, 1/30 s or 1/15 s will usually blur them significantly. However, 1/8 s or 1/4 s may be needed if they are walking toward the lens. Of course, all of this also depends on how far from the lens the person is. A closer subject will blur more significantly than a farther subject. Remember that you need to keep the camera still in order for this to work effectively. That could mean a tripod or using the lowest shutter speed you can effectively hand-hold.
Of course, you don't have to keep the camera still either. You can move the camera with a subject to blur the background and keep the subject relatively sharp. This is called panning. It can take some practice to know which shutter speeds to use for different subjects, but can create images that will stand out from the crowd.
Exercise: Take your camera out and try to blur various objects. Vary the shutter speed to test the results. Try to work with different directions of motion, different lenses, and different subject distances. What does it take to freeze a person running across your frame? The wings of a bird taking flight? How slow does your shutter speed need to be in order to pan a motorcycle riding past? Are you able to hand-hold that 36 MP body at 1/8 s, or do you need a tripod?
Sean Molin's article not too long ago on the overuse of shallow depth of field is a good look at why you may want to vary your depth of field usage. Aside from the creative possibilities offered by keeping more in focus, lenses just aren't their best wide open. Compromises are made in lens production to ensure we're able to afford and carry them around. The Zeiss Otus 55mm f/1.4 is a prime (no pun intended) example of how price, size, and weight can increase as we increase the technical quality of a lens. Although some lenses are made without regard for these parameters, the majority are. This means we need to understand our lens and how it behaves at certain apertures.
Let's use the old Nikkor 50mm f/1.4 AF-D as an example. The lens opens to f/1.4, but in my experience, there is very little sharp at this aperture. Also, the haloing caused in a backlit scene at wide apertures renders images that are unusable for many purposes. The tradeoff in stopping this lens down is that by f/2, the out-of-focus areas degrade (especially with pin lights, where you will no longer see "bokeh balls" but heptagonal rendering of your formally lovely circles). The sharpness of this lens also begins to fall apart by f/11 (especially with today's high resolution sensors) due to the effects of diffraction.
This is not to say you shouldn't get yourself a copy of this lens, but to say you should understand its strengths and weaknesses and learn to exploit them. As I wrote in my first article on Fstoppers, the 58mm f/1.4G is one of my favorites because of its heavy vignette when used wide open and overall dreamy softness. This is not for everyone or for every application. But understanding this allows me to exploit it.
Exercise: Take out the fastest lens you own. Choose a subject and background type that you commonly shoot, and work in light you normally work in. Start wide open, and gradually stop the lens down, making one frame every stop (or third of a stop if you want to see a slower progression of change) until you reach the minimum aperture. Open these up on your computer and look for differences in sharpness, contrast, and of course, depth of field. What happens if you repeat this exercise at a different subject distance?
It may seem that focal length is a reactive choice when you first start out, but there is much more to it. Your focal length plays a huge role in determining your depth of field and the amount of distortion in your frame, but it also allows you to include or exclude things from your frame. With composition often referred to as "the art of exclusion," this is a concept we should spend some time with.
The shorter your focal length, the wider the angle of view you will get. This brings about a lot of changes in your image, but the most noticeable right off the bat will be inclusion. A wide angle lens includes a lot more information. It also makes things closer to the lens appear a lot larger and those farther away, much smaller. This can be an advantage or a disadvantage, but it pays to understand how it works.
Longer focal lengths achieve the opposite, they flatten the scene as the focal length increases, giving a more two-dimensional feel. They also have the effect of making objects in the scene render without any of the size distortions that shorter focal lengths introduce. One of the most important things a longer focal length lens can do is exclude things from your frame because of its narrower angle of view.
Exercise: Take photographs of a subject at different focal lengths. Try to keep the subject the same size in your frame for each image. At 24mm, you will need to be much closer to your subject than you will at 135mm, for example. What effects do the different focal lengths have on the look of your subject? How much of the background is visible? What happens to the depth of field?
Your camera manufacturer will list the ISO sensitivities your camera is capable of. However, it's not always a good idea to use them with abandon. Although things are night and day from what they were a few years ago (those times when people were switching to the Canon 5D just so they could use ISO 800 and 1600), there are still tradeoffs to be had. Visible noise is part of the problem, but that can be fairly well compensated for using software. The things that software cannot compensate for are loss of color and loss of dynamic range. Certain cameras are better than others at this, but it still bears a thought. Keeping your ISO as low as possible will ensure you get the most from your camera's sensor.
Also, be aware that when you get extremely high in ISO, especially in low light, you may see the effects of signal amplification in shadow discoloration. This usually manifests itself in extremely purple shadows with no detail retained. This could make or break an image for a wedding or event photographer.
Exercise: Shoot photographs of the same dimly lit subject on a tripod for easy comparison. Start at your lowest ISO and work through to your highest. Note the changes in both dynamic range and color rendition. Now, go back and shoot the same images, but underexpose them by one stop. Now, shoot the same sequence and overexpose them by one stop. In your software of choice, bring the overexposed and underexposed images to the same level as your well-exposed images, and compare the visible noise, color degradation, and shadow and highlight details. Does your sensor respond differently when you overexpose or underexpose? Would it be better to shoot an underexposed image at ISO 800 and push it in post? Or would it be better to shoot a perfectly exposed image at ISO 1600? Which produces better colors, dynamic range, and detail?
Your camera may have several different focus modes. These will usually be something like AF Single, AF Continuous, and AF Auto in most modern cameras. AF Auto is usually similar to the focus modes found in compact cameras, and allows the camera to decide what to focus on, so I will not cover it here.
AF Single will focus once until you ask the camera to focus again, whereas AF Continuous will continue to focus until the focusing button (shutter half-press or back button) is released. These two settings can make or break an image.
You see, AF Continuous may seem like the best setting for all cases when you read the previous sentence, but it can be set to tolerate a certain amount of focus error (and is usually set this way by default) in order to keep your shutter firing as quickly as possible. This is fantastic when you are shooting smaller apertures or when critical focus is not absolutely necessary. However, AF Single will check and recheck to make sure it is in focus before releasing the shutter.
It is for the above reasons that I switch between these modes multiple times per session. When working with young children at play, I will almost always be in AF-C mode. However, once I start on formal family images, it's straight to AF-S mode. This way, I can focus once, lock focus, and shoot as many frames as I need to without worrying that AF-C mode may slip focus away from my subjects.
Exercise: Test your camera's ability to focus on both moving and stationary subjects using both AF-S and AF-C modes. Which one yields more in-focus images of moving subjects? How well is your AF-C mode able to keep up with quickly moving subjects? By examining the images you shoot on your monitor, you'll be able to see the threshold for getting sharp images with your camera.
The important thing will all of these is to experience their limits for yourself and learn how your gear works. All of these things will teach you and help you to get it out of the way so you can work on what really matters: conveying information with your frames. Know your tools.