Focus stacking was a popular technique during our online macro classes. If you want to increase your depth of field, and still keep a blurry background, focus stacking 20 or more images at F4 is the way to go with macro shots. But what about landscapes?
Cree and I were just in the Colorado high country photographing wildflowers. Columbine is the state flower, and there is plenty of it in the high country right now. I found a patch that made a good foreground, but I wanted to keep sharp focus on the background as well. F16 produced enough sharpness for the flowers, but the distant background went a little soft. To solve this issue I shot three frames at F16. The first image focused on the flowers, the second image focused on the middle ground, and the last image focuses on the distant mountains. I stacked the three images in Photoshop, and the result was the image at top. Sharp from foreground flowers to the distant mountains in the background. Focus stacking landscapes can be done with fewer frames and at smaller apertures when you are trying to get acuity throughout the shot. I used a 4 stop soft edge graduated ND Singh-Ray filter to reduce the brightness in the sky.
Have a great weekend!