With regards to the discussion on British galleries' rights to claim copyright over pictures of their PD artworks, I've dug up the relevant piece of legislation. It is, frankly, a very dumb piece of legislation, but in my non-lawyer opinion here are the relevant clauses:
From the British Copyright, Design and Patents Act 1988:
In Section 4 (1)In this Part "artistic work" means. (a)a graphic work, photograph, sculpture or collage, irrespective of artistic quality, ... "photograph" means a recording of light or other radiation on any medium on which an image is produced or from which an image may by any means be produced, and which is not part of a film;
From Section 17:
(1)The copying of the work is an act restricted by the copyright in every description of copyright work; and references in this Part to copying and copies shall be construed as follows. (2)Copying in relation to a literary, dramatic, musical or artistic work means reproducing the work in any material form. This includes storing the work in any medium by electronic means. (3)In relation to an artistic work copying includes the making of a copy in three dimensions of a two-dimensional work and the making of a copy in two dimensions of a three-dimensional work.
Not very promising.