Focus Stacking on Steroids

With the advancements in camera technology and software, focus stacking has never been easier. You can now even stack complex woodland photos without significant difficulty. In this article, I share how to approach such scenes.

Focus stacking has always been my choice for landscape and architecture photos requiring a large depth of field. I was never satisfied with the results obtained by stopping down the lens. Usually, I try to shoot at f/9.5 for the best compromise between overall sharpness and depth of field.

Because fiddling around with the hyperfocal distance was slowing me down too much while still just giving me "acceptable" sharpness, I already made focus stacking a routine more than 10 years ago when I got my first full-frame camera, the Canon 5D Mark II.

In the beginning, though, it was difficult for some scenes. Moving elements were a big problem because of the time required to manually shift the focus between individual exposures. Stacking them involved a lot of retouching.

So often, the only way to get a photo after all was to stop down the lens and increase the ISO. This approach is good enough for the web, but the results often lack detail in large-format prints.

Even when touch screens later allowed for faster focusing and hence faster capturing of a stacking sequence, it often still took too long to capture all the photos. Placing the focus points too far apart could also still happen.

Automatic Focus Bracketing

The in-the-field process got much simpler as camera manufacturers began introducing automatic focus bracketing. It has quickly become one of my favorite features of the Canon EOS R5. At first, I was hesitant to use it, because it uses an electronic shutter resulting in 12-bit raw files versus the 14-bit raw files you get in the other shutter release modes. But tests and extensive pixel peeping showed that in the majority of cases, the difference in quality between 12- and 14-bit is negligible.

I have set up the R5 to use the most narrow focus increment during bracketing. It gives me the best results. Setting a wider increment might result in fewer photos and a quicker bracketing sequence, but blending the image will become more challenging.

Since the R5 considers the current aperture when adjusting focus, the number of images will usually range between three and six with the most narrow setting when shooting at f/9.5 with a wide lens. Having elements only inches from your camera or shooting with a longer lens will increase the number of images.

If you want fewer photos in a sequence because of moving elements, use a slightly smaller aperture of f/11 or f/13 combined with an increased ISO. While diffraction will already start to become noticeable, it is a compromise you will sometimes have to make, even with focus stacking. You'll still retain superior detail compared to an aperture of f/16  or f/22. If you don't know which aperture will give you the best results, capture two or three sequences with different settings and select the best one at home.

Lightroom AI Noise Reduction

Even the automatic bracketing of modern cameras can become slow when shooting around sunrise or sunset. Especially in the forest, this is a challenge when there is wind. Think of how long you'd usually expose a single photo to avoid movement in leaves and branches showing up. If you do focus stacking, you'll want all images in the sequence captured within that period or close to it.

Opening up the aperture is a solution to get shorter shutter speeds. But it also leads to more photos taken for focus stacking, which negates the effect. It means that you must use higher ISOs.

In the past, I always shied away from it. Even with the Canon EOS R5, I seldom went beyond ISO 800. Thankfully, AI allows us to overcome the technical limitations of our photography equipment. And since Adobe introduced their new AI denoise feature, we finally have a tool to clean up an image without introducing unwanted artifacts.

The comparison above shows a 100% crop of a woodland photo, taken at ISO 800 with the R5. The noise reduction is subtle and most noticeable in the leaves. The great thing is that no detail is lost, with no fine-tuning required. Lightroom's AI denoise tool has only one slider, and for ISO 800, setting it to a value between 25 and 35 is usually enough.

The comparison below shows a crop of a woodland photo taken at ISO 1,600. Here, you will notice the power of Lightroom's AI noise reduction. It's as if my camera just gained between two and three stops of ISO performance. It opens up many new possibilities, including even more complex focus stacks.

I show more examples, including a night image taken at ISO 6,400, in the feature video.

Helicon Focus

You can now capture a sequence of focus-shifted images very quickly by combining automatic focus bracketing and high ISOs. The only thing you have to do is put everything together. It is where tools like Helicon Focus still provide superior results to what Photoshop offers.

Last year, I wrote a detailed article about how to use Helicon Focus to stack complex woodland scenes. I also go through this workflow in the feature video.

Using Helicon, you can work with DNG files. It allows you to make raw adjustments in Lightroom even after the stacking.

Although the automatic stacking provides a great start, for woodland photos, you will usually have to spend additional time retouching in Helicon Focus. Try to get as good of a starting material as possible.

Whatever problems you cannot solve in Helicon still require retouching in Photoshop. But AI will help with that in the future.

Creative Adjustments

What's left to do are some creative adjustments. Use selective color, contrast, and dodge and burn to provide more depth to the image and guide the viewer. Sometimes, you can hide problematic areas of your stacking result through clever dodge and burn.

The image below shows a typical Photoshop edit for one of my woodland photos. Although the difference is not huge, the adjustments enhance the atmosphere and make the image more captivating.

Conclusion

Above, I showed how to use automatic focus bracketing, Lightroom's AI denoise, and Helicon Focus to create tack-sharp images in situations where a few years ago, it would have been nearly impossible or involved hours of post-processing. And we can only assume that those tools will get better in the future.