Bryan Bruce's 2010 documentary found no case could be made against Robin Bain that would justify the accusation that he murdered his family.
He said the aim of the YouTube video was to get some balance after Robin Bain's reputation was attacked during his son David's second trial and in Joe Karam's latest book.
"As Joe Karam has seen fit to continue to further denigrate Robin ... I felt it was important the public ought to have the benefit of what I learned about Robin Bain in the course of my investigation, that he was a kind, gentle and much-respected man," said Mr Bruce said.
Mr Bruce made the video from interviews he did during filming with people who knew the pair, and photos and video taken from old VHS tapes supplied to him by Robin Bain's brother, Michael Bain, in 2010.
The archival footage and interviews showed an image of a "kind and caring man", which was "a very different picture of Robin to the one painted of him at his son's second trial", Bruce said.
