Focusing on the subject is typically what we do to create a nice photograph. But by doing something very simple we can have only the subject in tack sharp focus and the background a “creamy .. dreamy” out of focus. This is called bokeh – which is the Japanese word for blur.
Bokeh is the amount of what’s in focus behind the subject. It’s directly related to depth of focus (DOF) which is what’s in focus both in front of and behind the subject. . With a shallow DOF you can have the subject’s eye in focus – but not their ear, with a deep DOF you can have 200 people in a group photo (basically) in focus.
But I’m focusing on how you can achieve a portrait which is more pleasing because you’ve focused on the subject(s) and blurred the background using a simple camera setting.
In almost every case the amount of bokeh you achieve is controlled by the aperture setting on your camera. Aperture is how far the lens opens when you push the shutter.
The larger the aperture number you choose the less light enters through the lens. This results in a deep DOF and and less bokeh. Which means that the smaller the aperture number you choose the more light will enter through the lens, the DOF is shallower and that creamy … dreamy blurred background is achieved.
The easiest way to get a nice bokeh is to set your camera’s aperture to the smallest number it will allow ( it will typically be something like F4 or F2.8). But you’re going to have to take the leap and photograph in either manual (the letter M on the camera’s dial) or aperture priority mode ( the letter A or AV on the camera’s dial). If your camera doesn’t have a dial, just look for these settings in the camera’s menu.
OK, so let’s say that the smallest aperture your camera will allow is F4, or maybe you have a DSLR (digital single lens reflex) camera with removable lenses and you have a lens with a F1.2 lowest aperture … pop quiz ! Which aperture will give you the best bokeh?
Here’s two scenarios – you’re photographing one person and you’re photographing nine people (three people in three rows) – but you want a pleasing bokeh in both pictures. The aperture setting you choose is going to be based first on how deep the subject is (DOF) and then on achieving the best bokeh possible. (subject in focus is the first priority).
The one person portrait is easy. Set the camera to the smallest aperture setting and that will help you determine the required shutter speed and ISO you need to get a correctly exposed picture. ( See my post on “The Exposure Triangle” if you want a description of how to do this https://danbusler.wordpress.com/2016/01/19/the-exposure-triangle/ )
The nine person group in three rows is a bit different. The group will be about 3 feet deep, so the DOF needs to be at least three feet. F8 is a great starting point for this group photo. Just remember to always focus on the center point of what you want to be in focus – in this case it will be the center row of people. Take the shot and see if everyone in the group is focus, is the background blurry? If not try a smaller aperture number or move back (increase the distance between you and the subject) and zoom in a bit.
Here are some examples of how using a large aperture ( like F32) increases DOF and how using a smaller aperture (like F2.8) produces a shallower DOF and better bokeh
Canon 70-200mm zoom lens set to 70mm at F32 and focusing on the number 1. All the numbers are in focus, including the fence in the background. No bokeh here.
Canon 70-200mm zoom lens zoomed in to 200mm at F32 and focusing on the number 1. Just zooming in has added a little bokeh to the other numbers.
Canon 70-200mm zoom lens set to 70mm at F32 and focusing on the number 2. ( Focusing on the middle row) Everything looks basically in focus, including the fence in the background
Canon 70-200mm zoom lens set to 200mm at F32 and focusing on the number 2. Everything is basically in focus, but the other numbers are a little blurry, so there a little bokeh
Canon 70-200mm zoom lens set to 70mm at F2.8 and focusing on the number 2. You can see that the other two signs are a bit out of focus. But were not zoomed in, so more of the scene appears to be in focus
Canon 70-200mm zoom lens set to 200mm at F2.8 and focusing on the number 2. Only the subject is in focus and there is a good bokeh. This shows how DOF is how much of what’s in front of and what’s behind the subject is in focus.
Canon 70-200mm zoom lens set to 70mm at F2.8 and focusing on the number 1. Only the subject is in focus, the fence is a bit blurred. But this is not great bokeh.
Canon 70-200mm zoom lens set to 200mm at F2.8 and focusing on the number 1. Only the subject is in focus and there is a great bokeh. This would be a close up single person portrait setting
Note: If I had used a lens with a F1.2 aperture the bokeh would have been even better.
Dan Busler is a professional portrait, performance and event photographer with studios located south of Boston in Walpole MA. You can see more of his work at http://www.danbuslerphotography.com