Coal Tits?

I hung a block of Bill Oddie's "power feed" in the ash tree this morning and it has attracted what I think are coal tits. We've not seen them in our yard before. I've had my bird book out and I've been poring over the plates. Coal tits are very like great tits only without the blue stripe along the wing. I wish the little buggers would stay still for half a minute so I could be sure.