Just to clarify, I have never had any problem taking photographs in
the BL of non-exhibition items. For example the statues, tapestries
and paintings in the Foyer and main public spaces, the building itself
and artefacts on long term display (such as the Perkins D cylinder
press). Objects such as the philatelic collections on public display
next to the cafe have specific signs asking you to not take
photographs (due to light sensitivity and because some of the
artefacts are not out of copyright).
Of course, if I were challenged I would follow the advice given,
though as with any institution individual security guards or other
staff can make mistakes and might not be all that clear as to how to
interpret the official policy.
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