The Two Aspen at Beaver Pond, Sunset example showed frames shot conventionally along with a focus stack, demonstrating how conventional stopping down is just not enough, even at f/10 (or f/11 or f/13).
This aperture series is a combination presentation, showing performance (and depth of field) from f/1.8 through f/11, but it also includes a 3-frame focus stack at f/9. Set against single-frame f/9 and f/11 frames, it provides insight into depth of field limitations versus stopping down.
Includes images up to full camera resolution, and crops.
Landscape photographers really need the focus stacking toolkit in their bag of skills, because there is simply no way to obtain adequate near-to-far depth of field in this scene, and many others like it.
Ironically, the “deep depth of field” often cited for an extreme wide angle lens (e.g., 14mm) is counterbalanced by the typical requirement that a compelling image lens requires very close subject matter in order to maintain interest; this is one such example. Thus while a 14mm has great depth of field while stopped down to f/11, that is still not nearly enough depth of field for subject matter a few feet away to the far distance.