>>4484127In practice, focal length for macro just says how far away you need to be for a given macro ratio
You might need to be within inches away with a 30mm macro, or can be closer to a foot away with a 105mm
You need the reproduction ratio / magnification to see how "macro" a given lens gets, most are 1:1 or 1.0x
Extension tubes just let you focus closer, for more magnification
Totally depends on the lens for what will get you the most macro