People have different opinions. I personally far prefer to turn dry but successfully drying a big chunk or log section is usually difficult or impossible. If turning large things like bowls I think you are better off turning green ASAP. Either turn to finished size and let things warp or rough turn, dry, then finish turn.
BTW, since I like to turn dry wood I usually cut up green log sections into smaller turning blanks, seal well, and sir dry. It's easy to find those invisible end checks with a rectangular turning blanks - before use just cut off a thin slice of end grain with the bandsaw and bend it. The slice will break at any defects like checks and ring shake. Most dry without checks, but if present I just cut back a bit more until I get to good wood.
It sometimes takes years for even relatively small blanks to dry to EMC, depending on the size, temperature, RH, species, and particular tree. I dry on wire shelves in my shop with heat and air and track the dryness by weight.
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In the last week I cut up a tree's worth of Dogwood into four tubs of blanks; some will probably take three or more years to dry.
JKJ