Photo Stacking for Landscape

I have only ever used a very basic approach to post processing images. I am however interested in doing better with landscape shots.

My approach in the past has been to err on the side of sharpness when shooting landscapes but have not been willing to wander much into the diffraction zone..F16 and smaller for greater DOF .

I was thinking as an alternative approach to shoot at say F5.6F- 8 and then combine a series of shots with a variety of focal points from to back to make one sharp throughout shot. I know this is done but wonder what software would do this effectively and efficiently - ie without a complicated routine. Any ideas?

g

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