This tutorial is about how to obtain a large depth-of-field using focus stacking.
The main question is: Is it better to use a macro rail or is it better to vary the focus of the lens?
As Alex, I use focus stacking (or “deep focus fusion”) quite often and most of the time I just shoot a series of photos with varied focus instead of a series with varied distance, using a rail.
Until now I always thought, that approach is a bit dirty, because it introduces changes in the magnification, but often it was the only way, because the depth of the object was far too deep for any rail. Imagine for example shooting a landscape. :-)
But now, I wanted to know for sure what is the better method and and did some tests.
One thing I can say to start with: With complex scenes, it is a good idea, not to change the position of the camera!
But now let’s take a closer look: