What is depth of field (and how you can master it).
Have you ever seen a photo and felt like you’re staring across a landscape where you can see for miles? Or maybe there’s a person, tree, or object that somehow stands out from the background. Then you’ve experienced one of the core rules of photography: depth of field.
Depth of field is the area of a photo that’s in focus.
Depth of field is the area of a photo that’s in focus. More technically, it’s the distance between the closest and farthest objects that still appear acceptably sharp in a photo. Being able to control the depth of field allows you to direct the viewer’s eye where you want it. You can have a shallow depth of field or a large depth of field.
Now that you know what the concept depth of field is, here are some FAQs to help you learn and master this technique.
What’s a shallow depth of field?
Shallow or narrow depth of field is when only a small area of the photo is in focus. For example, if you’re shooting a portrait, you may only want the subject in focus, prompting a shallow depth of field. This can also work in low-light situations where you need to open up your aperture to allow more light in.
What’s a large depth of field?
A large depth of field is when you have the entire scene in focus. Most landscape photos use a large depth of field.
The circle of confusion.
This is an important concept when it comes to determining depth of field. The circle of confusion is the diameter of the focal point where the subject is in focus. If the object you’re shooting is larger than the circle of confusion, the parts outside it will be blurry.
Think of a portrait photo. There’s an area of focus (usually the subject’s face) that’s very sharp. The areas that begin to blur are outside the circle of confusion.
What affects depth of field?
Depth of field is controlled by aperture, distance to your subject, and focal length.
- Aperture is the opening in the lens that allows light to hit the camera sensor. The bigger the opening, the more light comes through and vice versa. In regards to depth of field, the bigger your aperture, the more shallow your depth of field will be. Aperture is expressed by the f-stop. The larger the f-stop number, the smaller the actual aperture is, therefore the depth of field will be larger. Larger number = larger depth of field. Smaller number = shallower depth of field.
- Distance, or how far you are from your subject, is another factor in determining your photo’s depth of field. The closer you are to your subject, the shallower your depth of field will be. The farther away you are — you guessed it — the larger your depth of field.
- Focal length is the primary measurement of the lens and how it magnifies an object. The longer the focal length, the more narrow the angle of view and the higher the magnification. The shorter the focal length is, the wider the angle of view and the smaller the magnification.
How do you control depth of field?
Understanding the factors that affect depth of field will allow you to control it to achieve the shot you want. For a larger depth of field, stop down your aperture, shorten your focal length, or move farther away from your subject. If you want a narrower depth of field, open up your aperture, lengthen your focal length, or move closer to your subject.
Will the focal point always be in the middle of the depth of field?
No, the focal point is never directly in the middle. The depth of field will be about one-third in front of the focal point and about two-thirds behind it.
What f-stop gives the best depth of field?
There isn’t one f-stop that will work universally for every photo. There are so many factors that go into determining what f-stop you should use. What’s the lighting like, where are you shooting, what are you shooting, what look are you going for? While one f-stop may work for one photo, for another it may not work at all.
How does ISO affect depth of field?
Adjusting your ISO will change how much light is required to properly expose your subject. When you change your ISO, you’ll have to compensate by adjusting your aperture or exposure, thereby affecting your depth of field. If you have a high ISO, the camera will have a smaller aperture, giving you a larger depth of field.
Mastering depth of field is vital to improving your photography. The best thing you can do is learn the factors that affect it and practice manipulating them to achieve different looks. Find what works best for you and your style.
