The lighting in the VASA museum is quite dim in order to protect the delicate exhibits.  Flash pictures seem not to be discouraged, but I can't bring myself to use flash on such a subject.  Besides, beyond about 10 meters flash is useless so I generally shoot 'available light'.  Consequently the exposure times are very long, far longer than I expected.  The beating of the photographer's heart is enough, in these circumstances, to cause a blurred image.