If you plan on going out in the zodiacs, and you are among photographers, bring a garden kneeling pad. Trust me, your knees will thank me later.
Make sure your waterproof pants are waterproof. Really. Mine weren’t and it was challenging at times.
Make sure your waterproof pants have very wide lower legs to fit over the boots that are so big and cumbersome you feel like an Arctic Yeti. You won’t be able to wear anything except thin long underwear as those have to go into the boots as well. Silk long underwear is perfect. Go get a script for Scolopomine AND Zofran. You don’t use them together, but just in case you have side effects from one….
And if you do get Zofran, bring a stool softener. Unbelievably important.
If you want to improve your photography skills, sign up EARLY for the photography group. My Camera Cowboys were wonderful. (And kind, generous, and encouraging).
Check weight limits on both checked and cabin luggage on your way to Ushuaia. They sometimes check and if you are over the limit, you will have to pay for the extra weight.
Two-prong plug adaptors work well but check with your ship. But you may very well need the slanted flat prongs.
Your ship may very well have a donation box at the end of the trip, so consider leaving things behind, especially the sea sickness medications. All of them. They can use them for the crew, but not for passengers.
Jupiter Currency Exchange on Rivadiva is the best for changing money. Don’t use your credit cards! Bring cash and get about double the ‘official’ rate at a place like Jupiter. Reserve a variety of new USD bills for those that insist on payment that way.