Focus Stacking: How To Create Front-To-Back Sharpness In Your Image

In this post, I'm going to explain why you should care about focus stacking and how to do it in the most efficient way.

You'll see just how easy it is to do it yourself.

The Challenge

Let’s look at two classic scenarios where focus stacking is used to improve image quality.

Scenario 1

You're right in front of an incredibly stunning landscape.

There are beautiful wildflowers where you are. It extends all the way to the mountains in the back.

The mountains look like giants guarding the land, forming the perfect horizon for the sun.

You took a shot.

No matter how hard you try, the wildflowers immediately in front of you are always out of focus.

What’s going on and what should you do? (we’ll answer this question later in this post)

Scenario 2

Let’s take the wildflower scenario again…

Except for this time, there isn’t anything out of focus in the immediate foreground.

You look at the scene...the mountains go all the way far back and merge with the sky.

The first thing that pops into your mind is hyperfocal distance…

You take out your smartphone, open the app and calculate the hyperfocal distance.

Then, you press the shutter release and thought you’ve nailed it!

But little did you know, when you view the image large on your computer, the mountains in the back are not as sharp as the foreground.

Sounds familiar?

What Is Focus Stacking?

Also known as focus bracketing or focus blending.

The concept is similar to bracketing exposure.

But in this case, the subject, composition and exposure settings remain constant throughout the shot.

What you change is the focus point.

You shoot a series of bracketed shots, each with a different focus point.

These images are combined in post-processing to create a single image. 

The purpose of focus stacking is to maximize the sharpness from the foreground all the way to the background without missing a spot!

In a way, the focal point of the image is “extended”. 

Remember the example in scenario 1? 

The immediate foreground is out of focus because it's too far away from the focus point. (the amount of "out of focus" is also depends on the focal length and the aperture).

But this can all be resolved with focus stacking.

Why Use Focus Stacking?

There are two reasons why camera techniques are invented.

One, to allow us to fully utilize the features of digital cameras to produce the desired image.

Second, to help us circumvent the technical limitations of our gear to capture better images.

For focus stacking, it’s the latter.

To dive in further, here are four main reasons how focus stacking benefits you:

1. Achieve Front-To-Back Sharpness

...each lens also has an optimal aperture (sweet spot!) where the image produced is at its sharpest.

Beyond that, it will suffer from diffraction and sharpness starts going down the slope.

2. Get The “Fresh Look”

Remember those shampoo TV commercials?

Whenever the camera zooms into the model’s hair, it always looks in focus (sharp!), shiny and kind of wet.

You can almost see every single stand so clearly...

Subconsciously, our mind tells us “wow, what a fresh look!”.

When we see a tack sharp photograph, we recall the same subconsciousness and therefore the same impression.

This is further reinforced and enhanced when we use focus stacking to maximize sharpness.

3. Extended Depth-of-Field

Depth-of-field (DoF) is the distance between the closest and the farthest object that appears sharp in the image.

There are two universal limitations to DoF:

1. Object very close to the lens will often be out of focus (also dependent on focal length and aperture). 
2. Although objects within DoF appear sharp, it actually falls off gradually as you move into the distance from the focus point even at the optimal aperture.

4. Macro Photography

That means trading off with DoF.

If you’re shooting a busy bee harvesting honey, you might only get its little head or wings in focus.

To get the entire subject in focus...yup, you got it…

Focus stacking!

Equipment You Need

It’s pretty simple really.

• A camera capable of shooting in manual mode and a lens with manual focusing (which you probably have already if you’re reading this article).
• A tripod - Unlike exposure bracketing where you can shoot with handheld, it’s impossible to focus stack without a tripod.
• Software - You need a software to blend the bracketed images together. This will be discussed in more detail in post-processing.
• Patience - I don’t want to put you off by saying the workflow is tedious...but it does take some practice to get used to it and become efficient. The bottom line is, be patient on your first few attempts!

How To Bracket Focus

A common challenge for beginners is not knowing where to focus when bracketing focus.

Here are three different ways to bracket focus.

The first two techniques share the same principles, just different ways of execution.

The third method applies to Canon users only 🙂

The Vertical Line Technique

The way I do it, I follow an imaginary vertical line so there’s no confusion!

Here are the steps:

With this technique, you literally won’t miss a spot.

The image will be guaranteed to be tack sharp throughout.

The Minimalist

Similar to the vertical line technique, the minimalist requires only three bracketed shots.

Start by following Step 1 to 6 above…

Instead of taking multiple shots with different focus points along an imaginary vertical line, you only need to focus the foreground, midground and the background.

The principles are the same, do it on the LCD screen (live view), in manual mode and manual focusing.

This technique does save you some time, but the main disadvantage is the potential of less coverage.

Magic Lantern

Post-Processing

This is where the magic happens.

There are two parts to it: (1) Align the images, and (2) Blend the images.

I use Adobe Photoshop CC 2019. If you use other software or an earlier version, the steps might be slightly different but the principles are the same.

How To Align Images

Lightroom + Photoshop Workflow

The reason for using both is simple.

Lightroom for organization and light editing, Photoshop for the heavy lifting.

Once you have highlighted the images you want to align in Lightroom, right-click and select Edit In > Open as Layers in Photoshop.

In Photoshop, select all the layers and go to Edit > Auto-Align Layers.

Select Auto in the Auto-Align Layers panel.

You can also check the box for Vignette Removal and Geometric Distortion if you haven't done so already in Lightroom.

Photoshop Workflow

If you don’t use Lightroom or have another software for organizing your images, you can first export them into a folder or desktop for the moment.

In Photoshop, go to File > Script > Load Files Into Stack.

Browse to select all the images and hit OK.

The rest are exactly the same as explained above.

How To Focus Blending

Once you have aligned the images, the rest is really easy.

By now, you should have all the images for focus stacking aligned and stacked in layers in Photoshop.

If, for any reason, you have deselected all the layers...select them all again.

Now, go to Edit > Auto-Blend Layers.

The Auto-Blend Layers panel pops out at this point.

Select Stack Images and keep the other two options below checked (as shown in the screenshot above).

Depending on how many images you have, this might take a while.

Just sit back and relax…because the hard work is done!

Other Software/Apps For Focus Stacking

Final Thought

If you ever wondered how to achieve front-to-back razor-sharp images in landscape or macro shots, focus stacking is the answer.

It has a rather small learning curve...and you can definitely streamline the workflow with a bit of practice.

Also, post-processing is rather easy compared to, for example, exposure blending.

How To Focus Stacking (In Summary)

Here' a quick run-through: 

For more tutorials on image editing technique, please check out the editing technique resource page!