Ripper Street began filming its third series last week in Manchester; the first time the production crew has moved outside Dublin. They were shooting outside the old Town Hall. Interestingly, given the announcement of the new Gothic incarnation of IHMN, part of Daniel Radcliffe's new Frankenstein film was shot there recently too.
The crew is moving onto Loughborough and then back to Dublin for the eight episodes of Series 3.
Filming continues until August for an Autumn premiere on Amazon's online film service and then on the BBC a few months afterwards (I would guess in its usual winter slot).
Some useful costume colour reference material here.