The Case For Using Shutter Priority in Street Photography
I know that “real” photographers use the Manual Shooting Mode. That choice is just not practical for most street photographers. There are some really good ones who shoot in Auto, including most of the group who are using mobile devices. Auto is not the right choice for me. I might consider using the Program mode which is auto except that you get to choose the ISO. There are no circumstances that would cause me to give a camera, other than one on a mobile device, a choice about ISO. When a camera makes a wrong choice about that, it is a really wrong choice.
If “real” photographers are not shooting in the Manual Mode, they generally choose the Aperture Mode. Of course, I am being a little facetious here. I guarantee you, for example, that real sports photographers do not very often choose either of these modes. But that is a digression. There is ample reason to choose the Aperture Mode. In a very concrete way, the Aperture, which is how wide the lens is open, controls how much light gets into the camera. If your lens is wide open, which for the lenses I use is an f/2.8, you get the maximum amount of light. Light is generally a sought after commodity in street photography, so what is not to love in choosing Aperture Priority? Well, there is this “yes, but...” How wide the lens is open also determines the depth of field. The wider it is open, the more light you get, but the price you pay is how much of the image is in focus. As a street photographer, when I make the decision about using Aperture Priority, it is never about the amount of light coming into the camera. It is always about the depth of field. If I am doing street portraits, I use Aperture Priority and open up that lens as much as possible so that the background for my subject is not in focus.
I am a bit contrarian, which I think is consistent with choosing to be a street photographer. For the most part I choose Shutter Priority. How long the shutter is open also effects how much light comes into the camera. It joins ISO and Aperture to form the eternally confusing Exposure Triangle. How you keep those three balls in the air determines the exposure and effects the graininess and depth of field and the focus of your image. Of course, it is confusing. But the choice of using Shutter Priority is simple for me. What I really want in my pictures is for faces and/or scenes to be in focus. I am literally trying to stop motion to some degree in every single picture that I take. If the camera has to choose between light and focus, I want it to choose focus. I have a shot at fixing light in post processing. There is no fix for soft focus. Shutter speed determines the seconds or partial seconds a lens is open. The longer the lens is open, the more chance there is for motion blur. Using Shutter Priority also helps me manage risk. If I use Aperture Priority, there is really no limit on how long the camera will keep the shutter open in order to get enough light. Now, I will notice a shutter open 1/2 sec., but I will not notice one open 1/20 sec. There is almost no chance of getting an in-focus street photo when the shutter is open that long. In addition, I am not alerted to the problem because when the histogram flashes in the playback screen, it looks fine. Of course it does. The camera has gotten enough light by leaving the shutter open. On the other hand when I choose Shutter Priority, the absolute widest open aperture my camera can choose is f/2.8. If that does not let in enough light, the histogram immediately alerts me.
When I am taking candid street photography and often even street portraits, I want good focus. I most often use Shutter Priority and I recommend that you try it, also.
On a slightly overcast day, set your ISO to 400. Set your Aperture Priority at f/2.8 or the lowest Aperture your lens will allow. Set your Shutter Priority to 1/800, or if that produces pictures that are too dark, choose 1/400. Shoot pictures of something in motion, in quick succession, toggling between Aperture Priority and Shutter Priority. Compare the results. How does the setting change the light and the focus?
I believe Shutter Priority produced better focus. The Daffodils were swaying slightly in the wind.
If you post your results on Instagram or Facebook, please add the hashtag #dbwstreet so that I can see the post.