I always see kohanim remove their shoes before n'si'as kapayim, even those without leather, but not their socks. In other contexts I'm familiar with, socks are the same as non-leather shoes. For example, we can wear socks or non-leather shoes on the ninth of Av, and (I think) a kohen while working in the bes hamikdash can have no separation between himself and the floor, thus neither socks nor non-leather shoes.
- Are the kohanim I've seen correct to remove even non-leather shoes but not socks?
- what's the difference between socks and non-leather shoes? I mean: What's the definition of what must be removed, which includes even non-leather shoes but not socks?