Sometimes while shooting in photography, we aren’t quite able to blur the exact area of the image we want. We can only control the camera so much, and if you haven’t set the depth of field correctly or your lens doesn’t have those capabilities, you may need to learn how to blur a background in Lightroom.
Blurring the background can draw the eye to your subject and enhance the image as a whole by adding depth. Luckily, it is surprisingly easy to create a natural-looking background blur straight from Lightroom. These two methods work best to isolate your subject and blur the background (or foreground).
How To Blur A Background In Lightroom
To blur a background in Lightroom, click on the Masking Tool and choose Select Subject. Now in the Masking Panel, right-click on the Subject Mask and choose Invert to only select the background. With your mask complete, reduce the Clarity and Sharpness sliders to blur the photo’s background.
Let’s walk through that process together.
The first method to blur the background in Lightroom utilizes masking tools. These are a new addition to Lightroom, so ensure you’re working in the most up-to-date version of Lightroom Classic.
To start, open up the image you’d like to use in the Develop tab.
Now, you first need to isolate the subject from the background so we can edit around it. For this, I’ll use the masking tools. You can find the Mask icon between the Histogram and Basic tabs.
This icon opens the masking panel, which features several tools you can use to create different kinds of masks. For images with a clear subject, such as the image I’m using, the best masking tool is the Select Subject tool.
Other tools will likely be more challenging to isolate the area you’d like to blur. The brush tool, for instance, would work but is more time-consuming as you’d have to paint around your subject.
Select Subject is the best tool because Lightroom will automatically select the subject for you, and it is usually relatively accurate. Once you click Select Subject, the tool will take a moment and automatically select the subject of your image.
You’ll see the selection as a red highlight. If you don’t see the highlight, head to the Masks panel, which comes up automatically when the mask is created. Make sure the box is checked next to Show Overlay.
However, we want the background, not the subject, selected. So, we can invert the selection by heading to the Masks Panel and clicking the Ellipsis next to the Subject Mask.
Then, select Invert.
This inverts the selection and ensures everything but the subject is included in the selection.
Now it’s time to apply the edits to the mask to create the blur effect. Head to the side panel, and you’ll see all the adjustments you can make to the mask.
The ones you’ll be working with are Clarity and Sharpness. First, let’s begin with the Clarity slider and bring the toggle down a bit.
This will slightly blur the masked area, and you’ll be able to see the effect as you work. Drag the toggle until you’ve created a blur you like. I’ve brought the toggle nearly all the way back, removing most of the Clarity from the background and making the following effect:
Still, while the background is much less clear, it doesn’t quite look blurred enough. In that case, you can also use the Sharpness slider to further blur the background by making it less sharp.
This will result in an even more blurred background while the subject remains sharp.
You may notice some areas of the image that aren’t entirely blurred, particularly around the subject. This is likely due to Lightroom’s automatic selection of the subject. You can easily add back the blur by heading to the Masks Panel and, making sure the Subject 1 Mask is selected, click Add.
This will bring up the list of image masking tools and allow you to select another tool to use on your image and add to the current mask. The best one to use is the brush, as it gives you the most control over where you’re drawing.
Head back to the Develop panel, and you’ll see at the very top a few adjustments you can make to the size and functionality of your brush. Adjust the size as needed.
Then, ensure you check the Auto Mask box, as this will provide the most accuracy when drawing your selection.
Now, go around the areas that aren’t blurred yet with a soft brush. I will work on the area around the woman’s head, which has been left out of the automatic selection.
This will add these areas into the mask that creates a blur.
Now your image’s background should be blurred to your liking, with the subject still sharp. You can go on to edit your image as needed.
Keep in mind that the only downside to this method is that it creates the same level of blur across the entire image. This should suffice for most images, but if you’d like to make a realistic background blur, follow the next method.
How To Create A Realistic Background Blur In Lightroom
The second method uses the gradient filter to add a selective blur to the image. This blur will gradually increase as it moves away from the subject distance-wise, adding depth to the image and making the blur effect appear as if it came from your camera naturally.
Starting with the image open in the Develop tab, head to the Mask icon to view the different masking tools available. For this method, we’ll use the Linear Gradient.
Click the center of your image and drag down as if mimicking the natural depth-of-field, with the masked part going towards the top of the picture. It is best to keep the center point right in the center of your subject and drag the bottom line to the bottom of your subject.
You’ll see the mask appear as you’ve set it up, but your subject will likely be inside the mask, and we don’t want that. So, you’ll now need to remove the subject from your mask. The easiest and most accurate way to do this is to head to the Mask Panel and click Subtract. From the tool options that appear, click Select Subject.
After Lightroom takes a moment to identify the subject, the mask will appear with the subject cut out.
The select subject tool may remove other parts of your mask, in which case, you can click Add in the Mask Panel and then paint back the area you’d like to remain in the mask using the Brush tool (as outlined in the above section).
To create the blur effect, once you have your mask set up the way you’d like, head to the adjustments area and drag the toggles down for the Clarity and Sharpness settings.
Play with these two adjustments until you’re happy with the amount of blur created.
You’ll notice that the subject and the area in front of it will appear sharp and clear, while the areas farther away will be blurred. Because of the gradient effect, the blur will appear natural.
If you’d like, you can add another gradient to the bottom to create a more realistic depth-of-field effect in the foreground. Simply click Add in the Mask Panel, then select Linear Gradient.
Draw the linear gradient to start at the bottom of your subject.
Now you have an image with a natural-looking blurred foreground and background, leaving the subject in the center clear to draw the eye where you’d like it to go.
Now, if you’re the type of person that works between Lightroom and Photoshop regularly, learning how to do this in Photoshop can be worthwhile. I share the process of blurring a background in Photoshop in this tutorial.