Hello Jo,
I think it should be the actual Parish Register that will be online, maybe you will only get the page that your ancestor is on, it was images of the Parish Register that we transcribed from, so even if the transcriber has the name spelt wrong, it can be viewed online to check, I know of one mistake I made in the surname - Knuele - I thought it was Kneale - and it is not.
Averil