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How to Blur the Background in Lightroom: A Complete Guide

how to blur the background in Lightroom

If you want to give more emphasis to your subject, you must minimize the background. The best way to achieve this is in-camera; you can focus on the subject but pick a wide aperture and a long focal length for limited depth of field. The result is a sharp subject but a blurred, simplified background:

how to blur the background in Lightroom
The best way to blur the background in a photo is with a combination of focal length and aperture.

That is the ideal method. I’m going to teach you how to blur the background in Lightroom, but with the caveat that it is not the best way.

What if your image is sharp from front to back but the background now competes for attention? You didn’t think about it and made your shot with a smaller aperture, wide focal length, or both. Or perhaps you’re dealing with a smartphone image, where a small sensor size and a very short focal length almost always creates images with everything in focus.

how to blur the background in Lightroom
Smartphone photos typically have a deep depth of field due to the small sensors and very short focal lengths. The image on the left is straight out of the phone. The version on the right had the background blurred with Lightroom to put more emphasis on the subject.

If you failed to get a blurred background in-camera, your next best option is Photoshop – or another sophisticated editing program that supports layers, selections, and functions like gradients and Gaussian blur.

As for Lightroom: It’s a fair option. It will work, but using it to blur your background probably ought to be thought of as a “rescue mission.” I don’t want to discourage you – Lightroom often can produce a very acceptable blur – but I’d strongly encourage you to shoot multiple images during your photo session and vary the aperture if you think you might want to soften the background.

But all the coulda, woulda, and shoulda regrets over how you might have made a better in-camera capture don’t count when the session is over, the images are already made, and Lightroom is the only editing tool you have.

So let me show you how to blur the background in Lightroom.

How to Blue the Background in Lightroom - The rock chuck
“Chuck” the rockchuck blended in a bit too much with the background. Using Lightroom, I blurred the areas around him to simulate a shot with a long lens and a wide aperture.

Two major steps

There are two major things to consider when blurring the background in Lightroom:

  • What area(s) you want blurred
  • The kind and amount of blurring you want

The what and how of masking

In Photoshop, defining the area you want to work with is typically done with selections. There are a variety of tools to create selections, and once you’ve made them, you’ll typically see the “marching ants” – the animated dotted-line border that defines your selected area.

But in Lightroom, there are no selections, and you’ll never see the ants. Instead, Lightroom uses what it calls “masks” to allow you to select areas where you want effects applied.

There are three local adjustment tools you can use in Lightroom to select areas and apply masks:

Blurring the background with a Graduated Filter and the filter brush

statue in the park with and without a blurry background
This statue photo has a busy background. Background blurring techniques in Lightroom can help keep more attention on the subject.
statue in the park
Step 1: Drag a Graduated Filter from the right edge across the entire image. The Mask Overlay is turned on (in green).
statue in the park with masking
Step 2: With the Graduated Filter still selected, get the filter brush tool. (Find the word “Brush” at the top of the editing panels and click that, not the picture of the brush). Either hold down the Alt/Option key while you work so the symbol inside the brush is a “-” sign or click the Erase option. Erase portions of the mask you don’t want to be blurred. The Auto Mask option can be helpful to find edges.
statue in the park with masking
Step 3: Finish erasing the portions of the subject you want to be sharp. Then think about other areas that would be sharp if you had shot with a limited depth of field, such as the foreground. Erase those areas, too, making sure to use a very feathered brush with a low flow. After your image is masked, drag down the Sharpness slider to create the blur. (It’s good to toggle off the Mask Overlay here so you can see what you’re doing; just hit “O” on the keyboard to toggle it on and off.)

It’s probably best to think of your filter brush more as an airbrush than a paintbrush. There are four settings you can use to control its application:

  • Size: Changes the size of the brush. Roll the mouse wheel, use the left and right bracket keys, or use the slider.
  • Feather: Changes how hard the edge of the brush is and how rapidly the effect falls off. Use Shift while rolling the mouse wheel, Shift and the bracket keys together, or the Feather slider.
  • Flow: Controls how quickly the effect is applied with each stroke of the brush. Use the slider to adjust the flow, or with the brush tool selected, change the flow with the number keys on the keyboard. Using multiple strokes will build up the effect.
  • Density: Controls the maximum opacity of the brush effect. For example, if the Flow was at 100 but the Density was at 50, one stroke of the brush would apply the effect at 50% opacity.

It is possible to simply select the Adjustment Brush, drag the sharpness slider all the way down (“reverse sharpening”), and start painting away on your image, watching the painted sections become more blurred. (You are still creating a mask this way, but you will not see it unless you turn on the Mask Overlay).

The Adjustment Brush method might work fine if you don’t mind being imprecise about how finely the blur is applied, but it is not the best method for finer work.

Radial Filter

The Radial Filter has a shape that is restricted to circles and ovals. The effect radiates out from the center of the spot where it is applied. You can control its size, feathering, and orientation.

Using the Invert checkbox, you can also control whether the filter effect occurs outside the oval (the default), or inside the oval (if the Invert box is checked).

How to blue the background in Lightroom the Radial filter
Blurring the background with the Radial Filter is a three-step process:

1) Mask the entire image with the Radial Filter. (Turn on the Mask Overlay to see where the mask is applied.)

2) Use the filter brush to erase portions of the mask you want to remain sharp.

3) Slide the Sharpness slider to the left for reverse sharpening (softening) of the masked areas.

The image on the left is prior to masking; the image in the center shows the masked area after removing the mask on the barn; the image on the right shows a blurred background.

The Overlay option

Being able to see where you’ve applied a mask makes things easier, so turning on the Mask Overlay option is a good idea. This can be done by either checking the box at the bottom of the screen labeled Show Selected Mask Overlay or by tapping the “O” key on your keyboard.

You can cycle through various overlay colors (which can help to make your mask stand out over different photo colors) by using Shift + O.

landscape of rainforest with and without background blur
This background blur was created by simply loading the Adjustment Brush with the Sharpness slider turned down, then painting over the areas I wanted to soften. I added a Radial Mask with a slightly raised exposure to the fern to give added attention there.

Modifying masks

Though the Adjustment Brush, Radial Filter, and Graduated Filter are the only tools for applying masks, there are other tools for modifying them.

  • Auto Mask – Checking this box while working with a brush will help the brush find edges in your image and can make masking much easier.
  • Erase – You can use the Adjustment Brush to paint on a mask. When doing so, you will see a “+” symbol at the center of the brush. Clicking the Erase option will change the symbol at the center of the brush to a “-” symbol so that you can erase portions of the mask you already painted on. You can also easily switch from painting to erasing by holding down the Alt/Option key.
  • You can add or subtract from Graduated Filter or Radial Filter masks with the filter brush tool. If you are working with a Graduated or Radial Filter mask, you will see the word “Brush” appear to the right of the word “Mask.” Important: This is a different brush than the Adjustment Brush tool. It will allow you to add to or subtract from your existing Graduated Filter or Radial Filter mask.

Range masking

Lightroom has recently added what is called the Range Mask.

With Range Masking, you still apply an initial mask using the three tools mentioned above (the Adjustment Brush, the Radial Filter, and the Graduated Filter). But by turning on Range Masking, you can control more specifically where the mask is applied.

The Luminance Range Mask will allow you to selectively apply a mask to a range of luminance (brightness) in the photo, while Color Range Masking allows the mask to be applied to a range of color (hue). Being proficient with the Range Mask will serve you well as you become a more skilled Lightroom editor.

Range Masking and blurring with Lightroom
Clockwise from top left: 1) the Before image. 2) The background selected with the Color Range Mask. 3) The background blurred with one blur layer. 4) The background blurred with three duplicate blur layers.

Learning how to create a mask to work with the areas you want is the most important part of how to blur the background in Lightroom. Take time to carefully apply and fine-tune your masks. How convincing your final image will be is highly dependent on the careful application of your mask.

How to blur the background in Lightroom - Before
This is the original edited image. It had been foggy earlier in the day, and I wanted to emulate that look.
How to blur the background in Lightroom - graduated filter applied
I first brought in Graduated Filters from both the right and the left with the Sharpen slider down to about -28.
How to blur the background in Lightroom - graduated filter applied
I then brought another Graduated Filter down from the top with the Sharpen slider all the way down to -95.
How to blur the background in Lightroom - adjustment brush applied
I then added some additional masking with the Adjustment Brush tool, and I dropped the Sharpening down to about -33.
how to blur the background in Lightroom blurry background forest
Here is the final result with some additional negative Dehaze added to my masks.

Creating the blur

Creating your masks will determine where your blurring effect is applied. It’s the more time-consuming and critical step.

But these next steps will determine how the blur looks.

Let’s say you have a person in your foreground as the main subject. You want them to be sharp, but you’d like to blur the background. Using the masking tools and techniques I’ve outlined above, here’s how I’d approach the image:

  1. Drag a Graduated Filter across the image so the entire scene is masked.
  2. Use the filter brush tool (the one that’s part of the Graduated Filter) to fine-tune the mask, erasing portions over the subject, adding back as needed, and perhaps also using the Auto Mask feature to help you better mask near the edges.
  3. Now, with your Graduated Filter selected, drag the Sharpness slider down, perhaps all the way to the left.
  4. See if dragging down the Clarity slider a bit helps achieve the blur you want. Use this more sparingly than the Sharpness slider as it can create a strange look if applied too strongly.
  5. Play with the other sliders to see what effect they might have. Remember that each slider will only affect the masked area.

Double down on the blur

You might find that even if you drag your Sharpness or Clarity sliders all the way to the left, you still aren’t getting the amount of blur you’d like. Time to double down.

Once you’ve added the sharpening or clarity effect, right-click the pin and hit Duplicate. A copy of the adjustments will be applied on top of the existing adjustments, and the blur will be multiplied.

Still not enough? Repeat and duplicate again. You can make as many duplicates as you like, slowly building up the effect.

how to blur the background in Lightroom man with bike
Top left: The Before image. Top right: The mask applied. Bottom left: The background blurred with one pass of reverse sharpening. Bottom right: The background blurred with three duplicates of the reverse sharpening adjustment.

When you blur the background in Lightroom, less is more

Let’s come back around to what I said at the beginning of this article:

Using Lightroom to blur your background is not the best way to achieve the look you’re after. Softening details with editing is a bit of fakery and cannot begin to truly reproduce the kind of bokeh blur achieved with a lens.

So instead of creating something that is immediately obvious and calls attention to itself, be subtle. If an untrained observer would say, “This looks like an editing effect,” you’ve failed.

reverse sharpening bike on prairie
Less can be more. Just a little reverse sharpening to the background and foreground simulates a narrow depth of field.

Spend whatever time it takes to create and refine your masks so that it’s not obvious where the edge is. Consider the different parts of the scene that should – and shouldn’t! – be blurred.

Then be sparing in your application of reverse sharpness and clarity. It’s always a good practice to take a break after an editing session to give your eyes a rest, then look at your image again later. You might even ask someone else to view the image. (They should not be able to tell that anything was doctored.)

police motorbikes in a line
Front-to-back sharpness or a simulation of limited depth of field? For this shot, there wouldn’t have been time to shoot it both ways, so the ability to blur the background in editing was useful.

How to blur the background in Lightroom: final words

In teaching you how to blur the background in Lightroom, I want you to be successful with your editing and make beautiful images.

So test out the techniques I’ve shared. And if you get good results, post some of your before and after images in the comments below!

Why should you blur the background of a photo?

You should always decide on the most important subject in your photo and use techniques to put the most attention on that subject. Sometimes backgrounds can be distracting, so blurring them while keeping the main subject sharp can be a good idea.

Is Lightroom a good application for blurring the background?

It works, but you will be using tools not especially created for this purpose. Adobe Photoshop or a different editing application with selections, layers, and Gaussian blur would be better.

Is there a Blur tool in Lightroom?

Not really. To blur backgrounds in Lightroom, you add reverse sharpness and reverse clarity over selected portions of the image.

What is the best way to blur the background in a photo?

The best way is to shoot your photos with a limited depth of field. Wide apertures and longer focal lengths would be the in-camera approach to the blurred background look.

Will the “Portrait mode” of newer smartphone cameras allow you to blur the background?

Yes, this mode actually takes multiple shots and combines them in-camera to create a blurred background effect. It might be better than what you can do in Lightroom, but it provides limited user control and is not nearly as good as what can be done with a traditional camera.

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Rick Ohnsman
Rick Ohnsman

Photography isn’t just a hobby, it’s an adventure! Photography is about sharing my personal vision. From the ’70s, with a film SLR and a garage darkroom, college work with 4×5 view cameras, Kodachrome slides and into the digital age, I’ve pursued photography for over 45 years. An enthusiastic member of the Boise Camera Club, I share this common passion and enjoy teaching new members. See my work here – on 500px and on instagram.

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