Focus stacking is a technique mainly used by landscape and advertising photographers. It can be done manually focusing at different points, or you can use a camera like Nikon D850 to get it done automatically in-camera.
Focus stacking is basically combining multiple images with different focus distances. Merging these images creates a final image, where all parts are in focus. The technique has two steps; the first step is the shooting, and the second one is merging the images via using a software, such as Photoshop. The first step can be done manually, but if you are shooting tethered in a studio, then you can use a third-party software like Helicon Focus Pro, remotely controlling your camera to automatically focus and shoot separate points. In some cases, when shooting outdoors, a tethered shoot may be hard to setup, so you may have to shoot each focal point manually. At this point, the cameras with built-in focus stacking feature might be handy for quick operation.
In this ten-minute video by Tom Mackie of Landscape Photography iQ, you will see how to use the focus stacking feature of Nikon D850 on-location. Mackie demonstrates the in-camera settings and how to select focus step width based on the subject.
To stack these images by using Photoshop, simply go to the Scripts menu under File, and then select “Load Files into Stack”. Here, you can browse and load the images and Photoshop will load them into the layers panel as separate aligned layers. The next step will be selecting all layers and using the “Auto-Blend Layers” command under the Edit menu. This will create layer masks based on the in-focus areas of the images and you will get the final look.
If you have any tips about focus stacking, please share in the comments section below.