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Understanding Background Focus & DeFocus for Smartphones



Guide - Focus & Defocus

There are times when you feel like you have miss-captured the most beautiful moment of your life, and you’ll never get a chance to capture it again. All because you didn’t have a DSLR with you instead you had to take captures with your smartphone. Well, no one can give you those moments back but we can certainly prepare you to be ready for the moments that would be coming in future. This tutorial would be your ultimate guide to teaching yourself just about everything about capturing those DLSR like photos on your smartphone. So, let’s dive into the details. First you have to understand what is the focus and defocus.

What is Focus?

It is a basic tenet of photography, without understanding the meaning of it; you would be just pointing cameras with no great results at all. Though, typically it’s hard to define focus without going into technical details, but we would try to stick as per the needs of photography. It is because of the optical properties of the photographic lenses that object that lies within the range of the camera would be reproduced clearly. Now if we have a need to adjust that range, then the process of changing the camera location is the focus. There are tons of ways on how you can adjust the focus of a camera accurately. The right focus can nourish the object and show great details while a bad focus would ruin the output. The camera lens focuses something it is seen clearly in the viewfinder, which is your display when talking about smartphone photography. The lens focuses the light on your target going back to the sensor so that the picture captured is clear.

What is Defocus?

It is a technique of blurring the background/foreground while targeting an object, defocusing either of them allows the subject to look more impressive. The devices like Lytro first made it happen other than the fact that DSLR cameras are made for it. It would do that using a matrix of microlenses over its sensor, and then the processor would generate images with a different focus on a same file. Though, a smartphone lacks in a hardware part, but you still can work around and emulate the kind of effect via a smartphone camera, which has a traditional lens and sensor combo, all thanks to the trick camera apps can pull off. You could just easily create DSLR-like bokeh effects the old fashioned way. The high-end smartphones may lack in offering fancy lens, but they usually make up in processing the photos. In short, the computational photography can be just as persuasive as digital single-lens reflex camera photography. To control the amount of defocus, you have to understand the four factors that shape it. These are aperture (f-number), focal length, focusing distance, and distance to the background. By using the correct combination of these four factors you can easily achieve the amount of defocus required.

  1. Aperture (f-number) : The aperture is defined by a number called f-number, the smaller it is, the larger the amount of defocus you could achieve. Therefore, remember that the smartphone cameras with low aperture numbers are a jewel if you are looking a smartphone to use the camera features of it particularly. While the large of a number means that the depth of field for defocusing would be small, and then you’ll end up with less impressive photos.
  2. Focal Length : The Focal length of camera lens also affects the amount of defocus it can produce, which is directly proportional to the focal length. Meaning the longer focal length produces larger defocus while shorter defocus would be there if the focal length is smaller. If you are using a zooming, then you can increase the amount of defocus by shooting at the telephoto side, which is for DSLR cameras while this can’t be achieved with a smartphone camera.
  3. Focusing Distance : Whereas the aperture and focal length are the important part of defocusing photography, the distance between the camera and subject is just as important too. Different distances give a different perspective, and, in this case, the less the distance between camera & subject, the better defocus it would provide. Of course, it is also applied to the smartphone photography, in terms of the macro shots.
  4. Distance between the Subject & Background : You have to remember that the amount of defocus is affected by the distance between the camera and the subject, as well as the distance between the subject and the background. The farther you have placed the background from the subject, the better defocusing you will achieve. This can be easily achieved by moving background objects that are not your target as farther as possible from the target object.


There will always be a demand for a better camera module or a technology to be used on a smartphone, so that it can mimic the results of DSLR cameras. But the fact right now is that smartphone cameras are not scalable like DSLR cameras. Though, that should not stop you to click photos from smartphones because they have their advantages in terms of faster processing and sharing. All these advantages can be explored by using various apps. There are many apps on Android as well as iOS offering defocusing features, or an all focus feature which is somewhat similar as it lets you alter the focusing on the image.


  1. Google Camera : Google Camera app was first exclusive to few of the Nexus devices, and then it rolled out the app for others, which is currently now a default app on Android Stock. The app offers a Lens Blur feature where it focuses on one fixed object and blurs the background. You can further edit the photo later and change the focus according to your needs. But remember to follow the instructions while taking photos. The object needs to be fixed, and you slowly need to raise the device keeping it centered.
  2. Sony Background Defocus : This is an exclusive Sony app that is unfortunately not available for other Android smartphones. This app works its magic by taking two photos of the object then after that you can select which area to be blurred. It also provides the option to adjust the blur level and offers clean UI if you’re a fan of the design.
  3. Selective Focus : This app is not available in Google Play Store but lands into this list because, it is available for Android smartphones from Samsung. Particularly on flagship devices like Galaxy S5, Note 4, Note Edge, as well as including the latest Galaxy S6 and S6 Edge. By launching Selective Focus on the Camera app, it will take number of shots and process them as well. After that, it will ask for whether you want a near focus, far focus or everything focused.
  4. After Focus : This is one app that has been in the Google Play Store for long time more than Google Camera or any other apps. And that one of the reason it is widely used. It does some old school defocusing rather than applying the automatic procedure. Meaning, you have to select the area by drawing where you want the image to be focused.


  1. Tadaa SLR : This is one of the simplest tools you can find on the iOS platform, available for devices running on 6.0 version and later. It allows you to shoot first, then select the Focus according to your needs. You can do all kinds of depth-of-field effect including the bokeh. It won’t be as good as DLSR cameras but would certainly good for social sharing.
  2. Dyfocus : Most of the popular apps for cameras are from individual developers, and this is too. The Dyfocus app helps you in creating defocusing effects on your camera captures. Remember that you can select two points of interests at a time while taking a picture. It is very easy to use this app; the developer has integrated clear instruction when you open the app for first time.
  3. Focus Twist : This is another popular app that would be a good front runner for your defocusing needs. This developer tries to make a community of photography enthusiasts with this app. As it allows you to share the images online as well as see the curated gallery contents with photos from world class photographers. This offers the same defocusing features that can be seen on the above apps but has an advantage to post images directly to social sites.

What We Suggest

There are things that you still need to consider if you want to make those captures. Even with great apps, good conditions and powerful cameras on smartphones, you’d still need to learn some techniques that would be helpful in making your adventures more memorable with incredible photos you’ll take along the journey. There are few points we have covered below that would help you in improving your photography skills. They are not too technical, well, most of them are just plain obvious, but each point has its impact.

Rule of Thirds

Eiffel Tower - Rule of Thirds

This is the most well know factor of the photography composition. The basic principle behind it that you should break down an image into thirds, both horizontally and vertically, thus the name, the rule of thirds. You’ll now have nine parts of the image. Notice this from a viewfinder or an LCD of your smartphone. Now consider placing points of interests in the intersections or along the lines, which would then allow the photo to be balanced and will enable the viewer to be more interactive of the photo. In learning the rule of thirds, there are two important points that you have to be asking yourself. First, what is the POI in the shot? Second, where do I want to place them intentionally?



One of the most important things to be considered while taking a photograph, you must use gridlines functionality if the app on your smartphone supports. Otherwise, you can get tons of free apps on Google Play Store or App Store that would allow you to use the gridlines on the camera app. While we asked you to imagine and break the photo in 9 parts using third rules. There is a strong need of gridline use if you’re going the professional way.

Get A Tripod

To make your photos stable, this is one of the most important things that you’ll have to consider, getting a tripod for stable shots. Though, if you’re a doing landscape photography then it should be your first thing you take out of that bag you’ve been carrying your camera in. But when it’s come to photography from a smartphone, it is not always that one would carry a tripod with them. But you should try to be steady when clicking captures via your smartphone. One help would be to lean your hands on a surface if available. Below is the list of some top tripods that you can get for your smartphones.

  1. ChargerCity
  2. Neewer

Good Camera Features

Hardware always plays an important part of the role in photography; you need a powerful lens and sensor to catch all the light from that moment. Software might be able to do some magic to your captures after, but it is the hardware that would be capturing the moment. So, it is advised that you should get a smartphone with a good camera and features like Optical Image Stabilization (OIS) to help you take better photographs. You can find easily by heading over to our PhoneFinder.

Instagram Filters

Not everyone’s a professional or need a feel to learn about the photography in order to take great captures. There are other ways like Instagramming your photos. If you’re just in for a social fun, then this is the best thing happened to you. Instagram has carefully selected some filters that can make your dull photos bright up. While talking about the defocusing, there is a feature of Instagram that lets you blur out some part of it. The interface is so intuitive that in few seconds you can create a defocus version of any photo and post it online to a community of millions.


In the end, it’s all about experimenting new ways to take photographs that can give you better results. The Great output requires great hard work, and if you’re into this for passion then you have to keep experimenting the angles, exposure, situations, and everything in every perspective possible. Because a good photo is better than a bunch of random photos, which can create an ultimate good impression to the world.


So, that was our guide for you to understand the basics on how you can achieve the background defocusing on your smartphone. Or if you are into a smartphone photography then you saw above that we recommended our PhoneFinder to search forbest camera phones. But if you’re more specifically looking for a smartphone with best low-light photography or Optical Image Stabilization, then you should head out to our articles on top smartphones with low-light camera capabilities and Optical image stabilization.

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