August 13, 2022
I have already written two articles about focus stacking here. The first article dealt with how I use automatic focus bracketing in the field, and in the second article, I shared my focus stacking workflow in Helicon Focus. To provide you with even more tools, I now show you how I combine focus stacking with exposure blending.
In the Field Workflow
I have to do this frequently because in addition to capturing everything from foreground to background as sharp as possible, I want to show the complete dynamic range a scene contains. And for many scenes, capturing it is not possible with a single exposure.
The Canon R5 can usually capture the dynamic range in the foreground and the middle ground of my landscape photos in one image without much of a problem. But for the background, multiple exposures are often still necessary.
Unfortunately, the R5 and other modern cameras don’t yet allow the combination of automatic focus bracketing and exposure bracketing. So, my workflow, which I show in the video above, is the following:
I capture a series of images focused on different points in the scene by using the automatic focus bracketing feature of the Canon R5, which many other modern cameras also have, or I can manually change the focus for a series of images.
I focus on the horizon and capture three bracketed exposures, separated by two stops, to capture the complete dynamic range. This is typically sufficient to achieve a clean blending result in post-processing.
The above order can be switched, depending on the scene. For example, you might photograph a glowing sunset where you first want to capture what’s going on in the sky and then perform the focus stacking.
I will also adapt the workflow if I need multiple exposures for other parts of the scene. If that’s the case, I don’t use automatic focus bracketing. Instead, I focus manually and keep exposure bracketing active the whole time.
Photo Editing Workflow
At the end of the video above, I show my old focus stacking workflow in Photoshop. But for a few weeks now, I do focus stacking in Helicon Focus, which is faster and gives me better results. But how can I incorporate exposure blending into this new workflow?
Helicon Focus does not support exposure blending, as it isn’t designed for it. So, I still need Photoshop for this part. In Lightroom, I first apply my typical raw adjustments to one photo and then synchronize the settings over all the stacked and bracketed images. Then, I try to equalize the brightness in the three bracketed exposures so that the dark and the bright exposures look similar to the other photos of the series. It makes the blending much simpler as I show in the feature video.
Exposure Blending in Photoshop
Next, it’s time to blend the exposures for the background. I select the three photos, right-click on one of them, and go to Edit In – Open as Layers in Photoshop, where I use a mix of standard masks and, if necessary, luminosity masks to perform the exposure blending.
Then, I flatten the three layers down to one and save the result. Because I opened the photos directly from Lightroom, the saved image will automatically appear in Lightroom.
If you don’t want to use Photoshop, you can also give the HDR feature of Lightroom a try. For architecture and cityscape photos, it can work pretty well. But be careful: I found that the HDR blending in Lightroom can introduce artifacts at high-contrast edges. If I try to extract all the details there, I sometimes notice aliasing. In Photoshop, on the other hand, I have much more control over such areas, which is why I prefer to do the blending there.
Combining Focus Stacking and Exposure Blending
Now, it’s time for the stacking. Helicon Focus allows me to perform the stacking on both DNG and TIFF files. Since I saved the blended photo as a TIFF, I have to also perform the stacking with TIFF files. That’s different from the DNG workflow, which I showed in my last article about Helicon Focus.
I load the exposure blended image and the photos taken with different focus into Helicon Focus by right-clicking on one of them and then selecting Export – Helicon Focus (TIFF). Inside Helicon Focus, I usually use Method B to stack the photos by clicking on Render. You can see my go-to settings in the screenshot below.
After the rendering has been completed, I do manual retouching, which is crucial. Here, I combine the result of the exposure blending with that of the stacking.
The algorithm selects which areas will end up in the final blend based on detail and image sharpness, and it’s possible that it already uses parts of the blended photo during the stacking. I can now paint in additional areas I want in the final image. The retouching brush makes this very easy by providing a preview and smoothing out the blend as I paint.
When I do the manual blending, I look for the transition between middle ground and background. After I find it, I fill in the rest. Here, it can be helpful to toggle the depth map display. It shows how the images of the series were merged by using distinct shades of gray. With it active, I can find where to look for the transition and which areas of the background I might have missed in my painting.
Once I’m satisfied with the result, I head to the Saving tab, save the image, close Helicon Focus, and switch back to Lightroom, which should automatically reimport the photo. I can now either apply additional settings in Lightroom or open the image again in Photoshop, where I like to apply some finishing touches.
Afterward, the final step is preparing the image for the web. Here, I have one more tip for you: Use the Web Sharpener by Andreas Resch. It is a free plugin for Photoshop, and it ensures that your photos will look great in your targeted web resolution. After spending so much time with the blending and stacking, we don’t want to lose details at the finishing line now.