Focus Stacking allows you to keep almost all areas of a scene in focus, producing amazing images.
What Our Eyes See and the Need for Focus Stacking
When we look at a scene with our eyes, like the mountains in the background or a tree in the foreground, everything appears in focus because our eyes will continuously focus from near to far as we gaze upon the scene. In the world of photography, the camera focuses on a particular object. Depending on how close or how far that object is in the scene, other objects will be out of focus on the image taken. You can do some things to limit the out of focus areas, but sometimes it is not possible, or not desirable to do so.
This is where a process called “Focus Stacking” comes in. This process allows you to keep almost all areas of a scene in focus, producing amazing images. In our landscape photography, we frequently use focus stacking.
How Does Focus Stacking Work?
Simply, one takes multiple photographs of a scene with varying focal points and then merges the in-focus portions of each photograph into one single, in focus. image.
Many imaging programs have the ability to focus stack images. The programs often work very well in many scenarios… except we find them often lacking when it comes to landscape photography. While one can whip out a focus stacked image in a couple of minutes in some instances, sometimes it is much more complicated and can take hours to produce an image.
Here are some focus stack examples.
The first example is a cut-away from a larger image from Cummins Falls. It is a simple 2-image focus stack. Compare the first two images.
In the first image, the rocks in the foreground are out of focus, but the waterfall in the background is in focus.
In the second image, the rocks in the foreground are in focus while the waterfall & people in the background are out of focus.
Combine the two images with the areas in focus, and you get the third image where the foreground rocks and the background waterfall are all in focus.
Image #1 Used for Focus Stack
Image #2 Used for Focus Stack
Final Focus-Stacked Image
Example #2 is where it becomes more difficult to focus stack. This is a cut-away of an image from Niagara Falls. While taking this photo we knew we wouldn’t like the finished image because there was no sun. But, it is a good example of a complex focus stack.
This focus stack introduces two new things:
1) Plants like to move in the wind, or any breeze. While the images look almost identical, the flowers, branches and stems are all off slightly, making this a difficult focus stack
2) The camera was so close to the foreground, that it needed to take 3 photographs..
The first image has the lilies in focus, the second has the plants behind the lilies in focus, and the third has the farther foliage in focus along with the waterfall.
In the final version, we mainly used Photoshop to do the work. It did a pretty good job. However, there are flaws that need to be corrected. Since this photo is not on our ‘A” list, we’re not going to bother spending any more time on it. Specifically, if you look closely at the reddish plant in the middle (or any plants in that section), you can see between the leaves (the water sections), it is blurry. If this were an ‘A’ list photo, we would take the time to fix this, and that is where Focus Stacking can take hours. Since it is not on our ‘A’ list, it will remain as is.
But the point: Focus stacking can be sometimes quick and easy, or sometimes time consuming.
Images Used (3) for Focus Stack
Image #1 for Focus Stack
Image #2 for Focus Stack
Image #3 for Focus Stack
Final Focus-Stacked Image