Back in the late 1960's/early 1970's, one of our neighbours was Alan Rothwell, who was a long-standing cast member who played Ken Barlow's brother David. We regularly got to see many of the Corrie cast close up, and they fell into one of two camps - playing themselves or playing the complete opposite to their screen persona.
Two who fell into the latter category were Jean Alexander (Hilda Ogden) and Violet Carson (Ena Sharples). Jean Alexander was a very refined and elegant woman, totally unlike Hilda Ogden. Violet Carson was just the loveliest person, with a beaming smile, so unlike the sharp-tongued, unsmiling Ena Sharples. Margot Bryant, who played the inoffensive Minnie Caldwell, could be quite sharp-tongued though apparently.
But most were just the same on and off screen, including Bill Roache. I was at the studios one time and we were having a cup of tea in the restaurant when he came over with his wife and joined us. He was Ken Barlow (or Ken Barlow was Bill Roache) 100%.