They took his wrist binders off before he was lowered. Why would we need everything spelled out with Han putting his hands up like that? He did that when he was further down in the chamber, so why is it necessary to see it? And I have always loved that Vader's helmet blows slightly in the wind, it shows just how windy it was there and kind of reminds us that he is just a man in a mask and the man he once was is still in there.