Whether you shoot from the hip or bring your camera up to eye level, being able to pre-visualize a shot is one of the most important skill every photographer should learn. Unless you’re shooting in a studio with all the time in the world to play around with lighting and focal lengths, being able to know, even roughly, what your camera’s going to see ahead of time is a must. Even in the studio, time is usually money, and being able to create a shot in your mind before you even touch a camera will save you both; if you can switch focal lengths or lighting in your head you only have to do it once physically.
When shooting street it’s even more important to be able to “see” your shot ahead of time. If you’re shooting on a busy street, you might have only seconds or less to react to something interesting. As you bring the camera to your eye, if you already have the shot framed in your mind it’s just a matter of lining the camera up with the picture you’ve already taken in your head. For me, this is what makes photography an art and not simply an aptitude with some technology; the picture has already been taken before I press the shutter, after that the camera is just recording that picture. Yes, you can accidentally take a great image without thinking about what you’re doing ahead of time, just as you can operate your camera poorly and miss recording the scene you had laid out in your mind. It takes skill with hands and head to be consistently successful.
Being able to visualize the field of view of whatever lens you’re using is really just a matter of distances. Some people are great at visualizing distances, I’m terrible, so I’ve based my system around the size of the paving stones in Ottawa. It helps to have a friend along as a reference but the idea is to frame a series of shots through the viewfinder and memorize how far away your subject is in each shot. So for me, I know that with my 25mm lens, for an upper-torso shot the subject has to one paving stone away, two paving stones away is just enough for a full body shot and three paving stones away is a full body shot that will capture quite a bit of the surroundings as well.
For memorizing how wide the frame is just look through the viewfinder and find reference points at the far left and right of the frame, they should be right at the borders. Now put down the camera and extend your arms to point at the two reference points, this arc is roughly everything that will be in your shot. Do this often in different places. Your body has more than 6 senses, one of which is the often overlooked proprioception, the bodies sense of where it is. Proprioception is the reason you can touch your nose with your eyes closed or walk without looking at your feet and it’s a very strong sense. Once your body learns how far apart your arms are when you point at those landmarks on each side of the frame, you’ll be able to visualize your arms up in that position without actually raising them. Between those two exercises you’ll soon be able see the shot without using the viewfinder, it’s not 100% accurate, but it will improve your reaction time to a shot, and it’s an essential skill for shooting from the hip. I’ll remind my body of the position of my arms at the start of a day of shooting or when I change lenses and that’s usually all I need to keep a sense of that arc for the day.
Being able to visualize depth of field is much trickier. Depth of field not only changes from lens to lens, it also changes depending on your focal distance. Each lens also renders the out of focus areas, or bokeh, differently making it even more difficult to imagine how a scene will render at large apertures. For me, it’s enough to know what areas are going to be in focus and which aren’t, relying on lenses I trust to have a pleasant boken if I’m shooting wide open. If you’ve got a distance scale on your lens it’s just one more distance estimation, if you don’t, it’s a bit trickier. Most modern cameras without distance scales will have a DoF Preview button that will stop down your lens and show you what your film or sensor will see, remember that by default what you see through the viewfinder of an SLR is the lens wide open. You can also carry a DoF chart that shows how much is in focus for a particular focal length and aperture combination; just remember most autofocus systems don’t focus in the middle of the depth of field, most systems place a third of the focus area in front of where you focus and two thirds behind it.
Once you’ve got a handle on visualizing how your lens will capture a static scene you can go one step further and practice visualizing a dynamic one. In the studio you get to control everything but one of the things that makes street photography so exciting is the randomness and lack of control; on a busy street you can’t dictate where people walk, where cars stop, when the crosswalk is going to change, and you have to be able to flow with it.
Street photography can be a lot like hunting, you don’t aim directly at a moving target, you lead the target aiming for it will be, but in order to do that you have be able to play out the scene in your head. You have to look at all the moving elements around you and guess where they’re going to be, find your shot in this future arrangement of players and then move yourself so that you’re in position, waiting for the pieces to fall into place. Sometime you guess wrong and the pieces move in a way you couldn’t predict, and you have to be flexible enough to adapt as the scene unfolds.
Example: as you’re walking down the street, you see an interesting subject about a block ahead of you walking your way. There are quite a few people in between the two of you so you’re going to have to wait for the shot. Most of the scene is out of your control, you can wing it and hope that when you’re the right distance away your subject just happens to be in a good spot, but you can increase your chances by paying attention to the things you can control.
First thing to decide is where you’d ideally like to take the shot, what the backdrop of the photo is going to be. You know how far away your subject should be given your lens, you can’t control how fast the subject is approaching, but you can speed up or slow down to influence when they’ll be in range. There are other people walking both ways as well, so you have to guess where they’re going to be and guess where and when you’ll have a clean line of sight to your subject. What’s the lighting like where you want to take the shot? Part of deciding where you want to take the shot must be guessing if the light will fall on your subject in a flattering way. Make sure your exposure is set for where the shot will be, not where you are now, aperture priority can be handy in times of harsh light and shadows, and rapidly changing exposure values. And remember, you’re not just trying to record your subject on film, you’re trying to create an appealing photograph which captures all the static and dynamic elements around the subject. Being able to frame the future shot in your mind will increase your success rate tremendously.
Visualizing our shot ahead of time is probably one of the hardest skills to learn. Many areas of photography can be learned from books, the internet or other photographers; visualization is one of those skills that can only be mastered by doing. Luckily you can do it absolutely anywhere, at it doesn’t even require a camera. As you walk around every day, try looking for interesting shots, guess where people walking around you are going to move or pick out a person coming towards you try manoeuvring for a clear shot at a random distance. The nice thing about visualization is that once you get good at it, it become second nature, almost instinctual.