Shyish Albatross

On Sunday's Port Fairy pelagic trip I also photographed this bird that looks different from the nominate race of the Shy Albatross (or species depending on which side of the discussion re race or separate species you subscribe to). It's obviously an immature bird but the grey hood suggests to me Salvin's Albatross Thalassarche (cauta) salvini but I am not familiar enough with this race or with variations in immature Shy Albatross Thalassarche (cauta) cauta.

any ideas welcome...
(click on an image for larger view)

UPDATE (31 Oct 2012):
The general consensus of opinion (thank-you to all those who emailed me) seems to be that this is either a Shy Albatross (Thalassarche cauta) or  White-capped Albatross (Thalassarche steadi) with most suggesting that it is difficult to distinguish between them, particularly in immature birds, but there's a leaning towards T. steadi so I'm labelling this post that way for the moment. I am happy to take further suggestions/advice and will update this post accordingly if I get further evidence/argument to change this position.