Actually, these and a lot of my threads are beyond 1:1. These are probably in the range of 1.5:1 - 1.7:1....probably closer to the 1.7 mag. These are with 56mm of tubes in combo with the Tamron 180mm.. As to how I do it?? Just practice practice and practice. Steady hands and knowing when to fire when swaying into and out of the focal plane.
Lol...you know what, I took some shots for another forum of where I shoot...I will post them up so you all can see how "normal" the areas I get 99% of my shots really is.