Image Composition Guide: Subject Isolation

Using Selective Focus to Define Subjects

By K David in Articles and Tips on May 5, 2017

In our ongoing series providing tutorials on photographic techniques, this article examines how to use your gear to achieve subject isolation. This article defines what it is, examines why it occurs, and presents creative examples that exhibit subject isolation in use.

Robert | K David | Pentax 67II and 105mm f/2.4, Ektar 100

As a technique, subject isolation helps photographers clarify what a photo depicts. This article looks at what subject isolation is, what it is not, the benefits it provides to an image, and how to achieve it.

What is Subject Isolation?

Bob | K David | Pentax 67II and 105mm f/2.4, Ektar 100

Subject isolation is an intentional use of selective focus. An ideal use of subject isolation has the image's subject in focus with the foreground and background out of focus and with no mixing of the in- and out-of-focus areas. Achieving subject isolation requires some understanding of how camera lenses work.

Leica iiib | K David | Pentax K-3 and FA Limited 31mm f/1.8

Tip: Practice taking photos specifically with this technique. Try practicing this on different subjects.

Understanding Lens Depth of Field

Takumar 105mm f/2.9 Depth of Field Scales

If you have older or manual-focus lenses, or new high-end lenses, you've probably noticed something that looks like the above configuration. These are depth of field scales and can tell you a great deal about the lens and the images it can take. The scales are read by combining data points from the aperture ring, scales, and focus indicator. You'll notice that the scales spread out equidistant and in a mirror arrangement from the focus indicator. Let's see more examples from this lens and a 28mm lens.

Sample DoF Scales | Click to Enlarge

On the left is a series taken of the Takumar 105mm f/2.8. The images on the right are of a Vivitar 28mm f/2.5. The top two images show a lens focused at infinity. In the lower three, let's assume that the lens is set to f/16. In the second scale image the 105mm lens focuses from infinity down to about 30 feeet. This is shown by the aperture ring being set to 16 and the focusing ring having infinity over one f/16 and the 30 feet mak over the other f/16.

In the third set of scales down, the 105mm lens is focused from 15 feet down to about 11 feet. In the bottom image the 105mm lens is focused from about 4.25 feet down to four feet. That illustrates how the closer the focal point is, the narrower the depth of field also is, even when the aperture is set to a consistent setting. Use the 28mm lens scales on the right to test yourself. Notice also that the depth of field is much greater with the 28mm lens at similar focal distances.

Tip: If you don't have a manual focus lens, pick up an inexpensive one. Third-party lenses are a good option. Use it to practice the relationship between aperture and focus and to learn how the lens communicate those data in relationship to depth of field.

Why use Subject Isolation?

Subject Isolation Comparison | K David | Minolta Alpha 9, Takumar 17mm and Vivitar 135mm

The photo above shows two images taken on the same day with the same camera and same roll of film but two different lenses and in two different styles. Click on the image to see a lager view. The image on the left was taken with a fish-eye Takumar at f/11 or f/16 to capture the entire scene. The image on the right was taken with a Vivitar 135mm f/2.8 at f/2.8 or f/4. The image on the right uses subject isolation to emphasize the photo's intended subject.

Headless Mary | K David | Pentax LX and 77mm FA Limited, Ultrafine Red Dragon

As a general rule, subject isolation serves to inform the viewer of the photo's subject in an unequivocal way. Subject isolation is a tool to communicate through the image with whomever sees the photo in the future.

Tip: Subject isolation, as a technique, is as old as photography. This is not a modern gimmick or fad. Subject isolation helps the photographer communicate with the viewer and, used well, this technique is one of the strongest tools a photographer can use in their work.

Subject Isolation vs. Shallow Depth of Field Images

Images with subject isolation can use a shallow depth of field, but they are not shallow depth of field images nor are they bokeh images. Here are samples to illustrate the difference between subject isolation and shalow depth of field images. Click on the photos for larger versions.

Hand Bells 1 | K David | Pentax K-3 and SMC-M 50mm f/1.4

Hand Bells 2 | K David | Pentax K-3 and SMC-M 50mm f/1.4

The two hand bell photos above show subject isolation, first photo, and shallow depth of field, second photo. The difference is in how the subject is handled. In the first photo, the entire subject, the first bell, is in focus with neither the foreground or background being in focus and none of the bell being out of focus. In the second image, the G6 bell's brass portion is in focus but the handle is out of focus. Because the entire bell is not in focus, and because that bell is the subject, the image qualifies as a shallow depth of field image.

Alex | K David | Pentax K-3 and Tamron 70-300mm f/4-5.6 at f/6.3 or f/8

The differentiating factor is whether or not the entire subject is in suitable focus. To obtain a subject isolation photo, the photographer needs to understand how to use their lens' depth of field. Photographers also need to understand how to recognize the difference between subject isolation and shallow depth of field. The following two photos present a subject isolation photo as well as a shallow depth of field photo. Take a moment to figure out which is which in each. The logic will be explained after. Click on the photos for a larger view.

Borde Collie | K David | Pentax K-3 and 77mm FA Limited

Trooper and Hope | K David | Pentax K-3 and 77mm FA Limited

If you recognized that in the border collie photo the image on the right uses subject isolation, that's correct. In the lower image, the photo of Trooper, on the left, uses subject isolation whereas the photo of Hope, on the right, uses a shallow depth of field.

The difference is similar in each shallow depth of field image: the subject's whole face is not in focus. In both of the subject isolation photos, the subject's entire face is suitably in focus.

Flora | K David | Miranda Sensorex and Soligor 50mm f/1.4 at f/2 or f/2.8

A subject isolation image can use a very shallow depth of field. In the above photo, the image has a very shallow depth of field but still isolates the subject. The image below, of a similar subject, is a shallow depth of field photo even though it was taken at a smaller aperture than the above photo. Two differences exist in these photos: image format and angle. Image format is discussed later in the gear section.

Purple Flower | K David | Pentax 645 NII and SMC-A 80mm f/2.8 at f/4 or f/5.6

Tip: Be mindful of your camera-to-subject angle to ensure that you have a subject isolation photo instead of a shallow depth of field photo. Keeping your subject aligned to your lens' focal plane will help isolate the subject from the background.

Great Horned Owl | K David | Pentax MZ-S and 77mm FA Limited

Foreground and Background Separation

Napoleon | K David | Pentax K-3 and Tamron 70-300mm

A key way to ascertain if a photo uses subject isolation is to examine if the foreground and background, when both are in the photo, are out of focus while the subject is in focus. This is easiest to achieve with telephoto lenses for reasons detailed later in the gear section.

Christmas Candle | K David | Nikon FM2 and 50mm AI-D f/1.8, Fuji Natura 1600

Tip: To improve your subject isolation technique, use older lenses that have focusing distance scales. Take a series of photos with a mid-image-placed subject and foreground and background. Shoot the subject across the lens' aperture range and, in post, see which aperture for the given lens achieves subject isolation the best. Note that this will change with subject-to-camera distance as well as with each lens.

Scrub Jay | K David | Pentax K and Takumar 500mm f/4.5, Kodak Portra 800

Achieving Subject Isolation: Gear

Subject isolation can be achieved with most any lens and in any image format. Some equipment, however, is more well suited for subject isolation. The following subsection looks at different gear and explains how and why gear can help achieve subject isolation.

Dan | K David | Hassleblad 500 and Zeiss T* 80mm f/2.8

Tip: When learning how to take photos that isolate subjects, practice with various lenses and shoot across each lens' aperture range. When testing a new lens, this is a good practice as part of learning how the equipment works.

Telephoto Lenses

Squirrel Monkey | K David | Pentax K-3 and Tamron 70-300mm

As a general rule, telephoto lenses are more well suited for subject isolation than wide and normal lenses. This arises due to lens physics. The longer the focal length of a lens, the narrower the depth of field (if you keep the framing the same). Recall earlier the vast differences in the depth of field scales between the 105mm Takumar and 28mm Vivitar.

Narrow depths of field contribute to subject isolation by preventing an image's foreground and background from being in focus. You can see this in action by looking at the focusing scale on a lens. Telephoto lenses' focusing scales are much more tightly packed than wide-angle lenses' focusing scales.

Tip: To test this, use a telephoto lens of 135mm or longer and a 50mm lens. Take the same photo with the same framing, both shots at f/8. The result will show the much narrower depth of field on the telephoto lens.

Image Format

Swing | K David | Graflex Super D 4X5 and Navitar 250mm f/4.5

For illustrative purposes, let's define a 24 x 36mm full frame format telephoto lens as 70mm to 250mm. Beyond 250mm, we'll consider the focal length a super telephoto. As noted in the previous section, telephoto lenses, in 35mm terms, are more well suited for subject isolation.

California Sister Butterfly | K David | Pentax 645 NII and 80mm f/2.8, Fuji Velvia 50

A lot of photographers will say that medium- and large-format cameras are better for subject isolation. That stems from the normal lens on a medium format camera falling between 75mm (645) and 105mm (6X9). 6X6 tends to have an 80mm normal lens and 6X7 a 90mm normal lens. 4X5 normal lenses are around 200mm to 250mm. Lager formats like 5X7 and 8X10 uses even longer lenses as their normal focal length.

Black Tail Deer Carcass | K David | Hasselblad 501 CM and Zeiss T* 80mm f/2.8 at f/6.3

With a normal lens in medium- and large-format images, subject isolation can be achieved along a wide array of apertures. Even at f/8 or f/11, a medium- or large-format camera can isolate a subject nicely. Throw in large-format-camera movements, and subject isolation at any aperture becomes endlessly achievable.

Ed | K David | Pentax 67II and Takumar 105mm f/2.4, Ektar 100

Subject isolation of medium- and large-format images also stems from the larger image circle. If a photographer puts an 80mm lens on an APS-C DSLR, full-frame DSLR or 35mm camera, or medium-format camera, the lens would provide the same depth of field at each aperture on each camera. The difference between the three formats is how much of the lens' image circle is used by the image medium. Using more of the image circle allows a greater appearance of subject isolation.

Lou | K David | Pentax 67II and Takumar 105mm f/2.4, Portra 160

The reason for this apparent increase in subject isolation is that using a larger image circle for the same subject allows capturing more of the background with the same subject magnification. This added background capture, which falls out of focus quickly, isolates the subject.

Tip: If you have the ability to try different formats, doing so will help improve your photography more than practicing with the same gear over and over. Experimenting with different classes of gear and gear that works with optical physics in different ways will improve the way you use your primary equipment.

Nick | K David | KW Reflex Box (1930s 6X9 fixed-lens SLR) and Ilford Pan F+ 50 at 25 ISO


Borzoi | K David | Pentax K-3 and 77mm FA Limited

Close Subject

Key to separating your subject from the background is having the background out of focus with the subject in focus. An easy way to achieve this is to get as close to your subject as you can. Recalling the depth of field scales from earlier, even at smaller apertures, the depth of field is minimal.

Days of Heaven | K David | Olympus Pen F and Zuiko 38mm f/1.8, Ultrafine Red Dragon

The photo above shows a blade of grass at the half-frame Pen F's closest focus point with the standard 38mm lens. Even stopped down to around f/4.5 or f/5.6, as this photo was, allows suitable subject isolation.

Tip: An easy way to achieve subject isolation, when the subject allows, is to get as close to it as possible and stop the lens down a few notches. This also improves the lens' sharpness.

Distant Background in the Negative Space

Drain Cage | K David | Hasselblad 501CM and Zeiss T* 80mm f/2.8, Ektar 100

Composing an image so that the negative space has a distant or semi-distant background facilitates subject isolation. This allows the lens to be stopped down and amplifies the subject's removal from its surroundings. This technique helps to replicate the way that peoples' minds process scenes with subjects that they enjoy seeing.

Lure Coursing Italian Greyhound | K David | Pentax K-3 and Takumar 500mm f/4.5 at f/11

Blank Background

Mary | K David | Olympus M-1 and Zuiko 50mm f/1.4

Using a blank background in the negative space can help give the appearance of subject isolation. Also, with blank backgrounds, the background can be relatively close to the subject, even somewhat in focus, and still provide the appearance of an isolated subject.

Frank | K David | Pentax K-3 and 31mm FA Limited

Tip: A background doesn't actually have to be blank. In the above shot, the background was a restaurant with windows and people. However, the light fom the bounce flash compared with the dark background in the restaurant allowed the background to be suitably dark as to appear black. Adjusting a couple of sliders in post eliminated some stray light from one of the windows.

Active, Blurry Background

Saluki | K David | Pentax K-3 and 77mm FA Limited

Having a background with blurry details that can still be interpreted can provide a sense of place and help anchor an image. In the above image, the background has a dog, indicating that the subject Saluki is one of many in the area, in this case a dog show. In the below image, taken with a Pentax 110, the image demonstrates that any format can have subject isolation but also shows that the image was taken outside in a cafe's open-air seating. The dog and the bush in the background provide that information while the coffee remains isolated.

Coffee | K David | Pentax Auto 110 and 50mm f/2.8, Lomo X-pro 200 Developed as C-41


To help you develop your subject isolation identification skills and, therefore, your ability to take images with subject isolation, we're including this five-question quiz. Take a look at the photos, determine if you think it uses subject isolation or shallow depth of field, and then click on the photo to identify whether you were correct. Reasoning is detailed after each photo.

Quiz 1 | K David | Pentax 67II and Takumar 105mm f/2.4, Ektar 100

In this photo the subject, the man in the portrait, is clearly separate from the background. He is entirely, from his shoulder to his hair, in focus while the background is blury and separate. In this image, the background is active and blurry, giving a clear sense of place.

Quiz 2 | K David | Pentax K-3 Tamron 70-300mm

As with the above photo, the subject, from beak to tail feathers, is in focus while the background is blurry.

Quiz 3 | K David | Hasselblad 501CM and Zeiss T* 80mm f/2.8, Portra 160

In this shot, only part of the bush is in focus. The focus is a narrow sliver of the subject, not the entire subject.

Quiz 4 | K David | Pentax K-3 and Tamron 70-300mm

Here you can see that, though the background is blurry, the focal point is from the front of the owl's beak to the eye on the right side of the image. The eye on the left side of the image is out of focus.

Quiz 5 | K David | Pentax K-3 and Tamron 70-300mm

In this photo, the subject is in focus from her shoulder through the back of her head. The foreground fence and background park, however, are completely out of focus.

Creative Uses and Inspiration

To end the article, we're sharing some samples that use subject isolation well. Each sample will discuss how it was achieved and the photo's intention.

Cairn Terrier and Owner | K David | Pentax K-3 and 77mm FA Limited

This photo uses subject isolation with a very crowded frame and a subject that is very much not alone. By using a telephoto lens, the image plane is also compressed, amplifying the sense that the dog is being crowded by its owner. The dog wasn't actually uncomfortable, just very tired.

Cactus | K David | Minolta Alpha 9 and Minolta 50mm f/1.7

If this image conveys a sense of being in the Wild West, then it accomplished its aim. Using the wagon wheel in the background, an unmistakable symbol of the West, the image is intended to convey that it was taken in an America West setting. When using the out of focus area in a subject isolation photo, you can convey a sense of place, time, or meaning.

Grasshopper | K David | Pentax MZ-S and Tamron 70-300mm, Rollei Color 200

This photo was taken with the lens in macro mode, or more accurately, close-focus mode. The telephoto lens' already compressed depth of field from 180-300mm, the lens' close-focus range, combined with the subject being at the lens' close focus means that the background, though only six or so inches behind the subject, is suitably out of focus at f/7.1 or f/8. Subject isolation is a great technique for wildlife photography.

Jaime | K David Pentax K-3 and SMC-M 50mm f/1.4

Perhaps no better subject exists for subject isolation than people. Taking portraits in a manner that separates the subject from the background, as noted earlier, replicates the way that the human brain sees people we like. It also flatters people by clarifying the intended subject. The trick is to have the entire person in focus, not just their eyes or part of their face, unless there's a specific reason to do otherwise. In this photo, the 50mm lens was stopped down to around f/4.5 or f/5.6.


Subject isolation is one of the oldest photographic techniques and persists because of its utility and aesthetic appeal for viewers. Using subject isolation well will help you, as a photograph creator, communicate the intended subject to viewers, create a firm focal point in the image, and provide visual interest. This technique helps the photographer communicate with their viewer and share their photographic vision.

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