One of the various methods to isolate or enhance your subject is to blur the background. Do you require a particular lens to do this? Without a doubt! In this post, we’ll look at a few techniques for creating those smooth, lovely backgrounds with practically any camera and lens.
Use a Wider Aperture
The aperture of a lens is the asymmetrical opening that regulates how much light enters the lens. The ratio of the lens’s focal length to the apparent size of the adjustable opening, represented by the f-number, such f/2.8, is used to describe it. A wider aperture results in a background that is more blurred, all things being equal. Let’s examine four images taken at various apertures to demonstrate this effect:
As you can see, smoother, blurrier backgrounds are best achieved with larger apertures like f/1.8 and f/2.8. If achieving this is your goal, “fast” lenses like f/1.4 primes and f/2.8 zooms are advantageous. Even while these lenses can cost more than their equivalents, you should be able to locate some affordable f/1.8 or f/2 prime lenses for practically any camera on the market.
Even if you want a blurred background, widening your aperture is not always a good idea. Why is that so? For starters, even if you prefer the way the fuzzy background appears overall, the depth of field may be too shallow at wider apertures to adequately focus on your subject. Additionally, as repeatedly demonstrated on Photography Life, a lens that is close to its maximum aperture frequently displays less sharpness and more aberrations.
Very fast portrait lenses frequently suffer from a loss of clarity at wide apertures, while more modern designs have much improved on this front. For instance, I would not experience the same hesitancy when using the Nikon 50mm f/1.8 S for Nikon Z cameras instead of the Nikon 50mm f/1.8G. the most recent 50mm f/1.8 prime lenses from Canon, Sony, and other manufacturers.
Robert Capa, the renowned war photographer, famously observed, “If your shots aren’t excellent enough, you’re not close enough.” As it turns out, moving closer to your subject often improves photographs and also enhances background blur. When you don’t have a quick lens, you should utilize this method. Let’s try getting closer while leaving everything else the same to see what happens:
Of course, getting closer has drawbacks of its own. It makes it more difficult to take crisper pictures by exaggerating problems like camera shake and missing focus. Additionally, drawing nearer completely alters composition and perspective. Perspective is a particularly important consideration for portrait photographers because getting too close to a person’s face may highlight nearby features like the nose. Or you might not want to approach very close at all if you are a nature photographer and you are ready to take a picture of a King Cobra.
Keep the Background Far Away
One of the greatest techniques to have a blurred background is to keep it as far away as you can. The House Finch in the following photo was very close to me, while the background was a forest behind a distant river:
When photographing animals, be mindful of the background and shoot from several angles to keep distant background objects from being in focus. The background was merely moved closer to the subject by half in the second photo of the example below:
It’s also critical to consider the type of background that surrounds your subject. Thin grasses might disappear pretty quickly, but major structures like thick trees will be visible even from a distance.
Use a Bigger Sensor
Can you blur a background by using a larger sensor? Yes, in some instances. In comparison to a smaller sensor, you may acquire the same framing by moving closer to your subject while maintaining the same focal length, aperture, and sensor size. This is a different version of coming closer.
A camera with a large sensor is not necessary to produce stunning blurred backgrounds, though. All cameras benefit from focusing closer, using faster apertures, and keeping the backdrop far away.
Use a Longer Focal Length
Can a greater focus length help you achieve a background that is more blurred? Absolutely. Background blur grows as you zoom closer.
Contrary to popular belief, this still holds true if you take a small backward step to make your topic the same size. Less of the backdrop will be in the picture with long focal lengths compared to shorter ones because of the higher magnification longer focal lengths provide. This gives the impression of a background that is more blurred. Here is an illustration of zooming in and then moving backward to maintain the same framing:
It’s reasonable to argue that you haven’t changed your depth of field because the background is similarly detailed in both images. However, from an artistic perspective, it is bigger in the 150mm image. The background appears to be smoother and blurrier. This is the outcome of using a longer lens, even though I backed up to maintain the frame.
You would see a closer view of the orange and a more noticeable difference in background blur if I hadn’t taken the second photo (similar to the example in the “get closer” section).
There is a limit to how much freedom there is in focal length selection since shifting focal lengths while maintaining the same subject framing alters perspective. For instance, many people love the perspective and framing options available in the 85mm to 200mm full-frame equivalent range for portraits of individuals.
Motion Blur and Long Exposure
By blurring the background with a slow shutter speed, you may employ motion blur to make the foreground more rounded. In the example below, I used a five-second long exposure in both pictures, but I physically shook the background during the second one:
This effect can be achieved in wildlife photography by panning while the subject is moving. For instance, shutter rates about 1/2500 are typically employed to freeze flying birds, but you can pan with the bird at 1/40 to obtain an intriguing blurring effect.
The area surrounding the bird’s eye can still be seen in some detail if you pan extremely closely with it, but the background will be heavily motion blurred. For further information, I suggest reading Dvir Barkay’s Guide to Motion Blur and Panning.
The general idea still holds true even if you’re not going for the complete panning appearance. When tracking a bird in flight, erring on the side of 1/500 second will soften the backdrop if there is a range of shutter speeds that will give you a perfectly crisp bird, such as anything between 1/500 and 1/8000 second.
Blurring in Software?
I hesitate to bring up software, but modern software techniques are quite advanced and can now create a blur that is more lifelike than before. I looked for a photograph of a Black-capped Chickadee with a cluttered background as an experiment:
Then, I applied a smartphone software that simulates the out-of-focus result produced by a genuine lens by using AI to construct a depth map:
Although I did have to manually change the depth map on the chickadee’s bill, the results are not bad considering that it was almost entirely mechanical.
Even more advanced are phones that generate depth maps as images are being shot, which are then used by algorithms to produce background blurring with more realism using relatively small sensors. You can also use a tool like Photoshop’s Lens Blur in post-processing.
The use of such equipment carries some risk. For instance, the chickadee image I showed earlier included some imperfections. Moreover, areas of the image that were in the same plane of focus as the bird appeared to be distant because they were blurry. I personally never use such postprocessing since I feel that it goes beyond what I consider to be natural photography, with the exception of basic tweaks like noise reduction, tone curves, and color correction. However, when utilized carefully, such instruments might yield interesting results. Ultimately, one must make a personal creative choice regarding them. Regardless of your choice, I do advise making as much of what you want in camera as you can.
To Blur or Not to Blur?
We now know that we have control over how blurry the background is. However, it should be deliberate how much blur is present. In other words, rather of always going for blown-out blur, you should select a level of blur that will complement your subject.
Less blur offers more contextual background and a contrast with subjects that are smooth, while greater blur highlights interesting textures and depth in your subject. Of course, some images don’t even need to have any blur. Photos without any background blur at all are frequent when shooting scenes like landscapes or architecture, however sometimes photographers go to considerable measures to avoid it.
To best capture your subject, carefully consider your background blur choices.
In this post, we’ve looked at a number of camera settings, compositional techniques, and even software tools you might use to create a blurred background. You can select the right amount of blur for your images with these approaches while still having fun. I would be interested in reading your comments if you have any ideas about blurring the background.
Learn more: Focus and Recompose Technique