Usually,when we take focus stacking pictures,screwing the macro rail or micrometer(used in high magnification) by hand are popular in focus stacking photograph.
But it’s hard to get precise step length and sometime it’s boring if there are a lot of steps.
WeMacro automatic focus stacking rail can free you from manual works with high efficiency.
Butterfly wing scale test
objective lens :Nikon BDplan 10X and 40X
camera:Sony NEX C3
10X: step length 6 micron
40X: step length 1 micron
Theoretical value when you set 1 micron as a step it will be 0.9375 micron.It will help in high magnification.