One of the most effective ways to make your subject “pop” is to use depth of field to make the background blurry.
In the example above, the eye is drawn straight to the flowers and the little girl’s dress because the background is completely blurred. This is a great way to get rid of distractions in the background.
In this example, I used depth of field to both separate the little boy from the background, but also to make his hands really pop. His hands are the point of focus, and you can see that his masked face is slightly blurry. This makes the eyes go straight to his Spiderman web-making hands.
In this example, I used the same effect in another way. I was intrigued by the level of detail in this Terracotta warrior, so that was the subject of the image. Because I don’t know the museum goer in this photo, I didn’t want him to pull the viewer’s attention away from the statue, but I did like how the amazed look on his face added some context to the image. I blurred his face just enough to keep the statue in the foreground the obvious subject, but not so much that we can’t tell exactly what it is.
People aren’t the only thing this technique works on. In this example, it’s pretty obvious that I was enjoying my morning coffee overlooking a lovely small lake, but the viewer’s eye still has somewhere to “land” on the coffee cup since that is what I chose to leave in full focus.
This effect is created through “depth of field”. To put it simply, you can change how much of the scene in front of you will be in focus. For landscape images, you often want a very large depth of field because you want everything in the photo to be in focus. To get the effect in these examples, you want a smaller depth of field so your subject is in focus and the areas in front of and behind your subject are not in focus.
So how do we control depth of field?
Depth of field is controlled by three things:
1. How close the camera is to the subject (the closer you are, the more shallow the depth of field)
2. The focal length of your lens (the further you are “zoomed in”, or the longer the lens, the more shallow the depth of field will be)
3. The aperture
The first one is pretty self-explanatory. If you want a shallow depth of field, you can get closer to whatever it is you want in focus.
Zooming in (or using a longer lens) will decrease your depth of field. So a 70mm lens will have a shallower depth of field than an 18mm lens, if everything else stays the same.
Aperture is part that needs a bit of explaining. This is the number you will see on your camera that starts with f. Lenses will also refer to this number. Aperture is the size of the opening in your camera’s lens, so the aperture affects how much light gets into the camera. More light=less depth of field. What many people find confusing is that a smaller f-number means more light is getting into the camera. So if everything else stays the same, a camera set with the aperture at f2.8 will have shallower depth of field than one set at f8.0. There is a mathematical explanation for why this is the case, and I might get into this another day, but for now just trust me: smaller f number=shallower depth of field.
All three of these things work together. If you change any one of them, the depth of field may change. We are going to focus (ha!) on the one that you change with your camera settings: aperture.
Here’s an experiment you can do so you can see the effects for yourself:
Put your camera into Aperture Priority Mode. (Canon cameras use Av for Aperture Priority mode. Nikons use A. If you have another camera brand or aren’t sure how to switch your camera to Aperture Priority mode, please check your manual.)
Find a subject to photograph. Put some space between your subject and your background.
Change the aperture (the f-number)to a low number. If you are shooting with the lens that came with your camera, the lowest available number may be f4 or f5.6. If you have a 50mm lens (and you should go out and get one if you can!) then you could go as low as f1.8, but for now, change it to f2.
Take a photo.
Your camera will have lots of different choices for aperture, but we are going to use the standard “full stop” f number scale for this exercise. Using the chart below, find the f-number that your camera is currently on. Then change the aperture to the next higher number in the list. Don’t change anything else – your camera will take care of that.
f2 f2.8 f4 f5.6 f8 f11 f16 f22
Work your way up the list, taking photos at each number. So you will end up with at least five, but maybe as many as eight photos.
Once you have all of your photos, take them to your computer and bring them into whatever photo editing software you are most comfortable with. You can tweak for colour and contrast if you need to, but don’t do too much editing.
Arrange your photos into a collage so they are in order, from the lowest f-number to the highest. Big Huge Labs has an easy to use mosaic editor with lots of options. You can even add text to show the aperture setting for each photo.
Take a really close look. What was the effect of changing the aperture? What do you notice about the object you focused on? What about the objects in front of and behind that object? How does this change from photo to photo?
You have just created your very own aperture cheat sheet! Now that you have seen the effects of aperture, challenge yourself to only shoot in aperture priority mode this week.
Post either your “cheat sheet” or a photo where you used the aperture setting to make your photo “pop” in the comments. I can’t wait to see your work!