Hello brothers and sisters, today I want to talk about the most useful camera mode while doing street photography. Yes, it’s the aperture priority mode. I only use manual mode for specific occasions such as long exposure landscape photography, because my camera would not understand what I am trying to do. For example, if I want to do a 30 second exposure to capture light trails at night, the manual mode would be the right mode. See the picture below ( the camera was mounted to a tripod).
Back to street photography, here I am talking about street portrait in which I want to have a shallow depth of field, so the object can stand out from its background. Second, shutter speed needs to be fast enough to avoid blurred images because the camera’s hand-held. The 24-120 F4 zoom lens is the ideal option since I only have two lenses; you know that the other one is the 50mm f1.8 prime lens. The zoom lens is helpful for composition. Therefore, I choose the aperture priority mode to ensure that I am shooting with aperture f4 which is the widest aperture of my zoom lens. In addition, I want the shutter speed doesn’t go lower than 1/250 second. Therefore, I choose an iso which is high enough to ensure the shutter speed will be faster than or equal to 1/250 second. Why 1/250 second? The value of shutter speed depends on the object. If the object is moving very fast, the shutter speed has to be fast enough to freeze the image. For most cases, shutter speed 1/250 second is fast enough for street photography. For a given set of iso and aperture values, the camera would determine a certain shutter speed to obtain the right exposure. For instance, I may set the iso value to 500 at noon of a cloudy day and the aperture value to f4, therefore, the camera determines 1/2000 second as the shutter speed. At this situation, I would have nice bokeh since the aperture is wild open, and also a clear portrait image because of the1/2000 second shutter speed.
The beauty of the aperture priority mode is that when the background becomes darker or I go from outside into a room, the shutter speed, for example, would automatically decrease from 1/2000 to 1/250 second in which I still can obtain a clear image without re-adjusting iso and aperture values. For most newly released cameras, iso 6400 can still produce very clean images. In some extreme lowlight situations like in a dim dinning room, I would use the 50 f1.8 prime lens and set iso to 12800. Shooting with f1.8, iso 12800 and steady hands, I am able to obtain sharp images with nice bokeh in very low-light surroundings.
In summary, aperture value affects the depth of field and the shutter speed under a given iso value. The aperture priority mode lets the photographer set aperture and iso values, and the camera determine the shutter speed. With a given set of aperture and iso values, the photographer can yield a safe shutter speed which is fast enough to obtain clear image. The photographer can pre-set a high iso value, so when the lighting is getting darker, the shutter speed is still high enough to freeze the object. With the help of the aperture priority mode, street photography would be easy and fun.