Kyle McAuley, 30, was found guilty of the murder of 28-year-old Kevin McCluskey in the early hours after 24 March at a flat in Greenock.
Officers and emergency services were called to the flat on Nelson Street around 5:45am where Mr McCluskey was found with serious injuries to his face and head.
He died at the scene.
McAuley, a former soldier, was convicted today following a trial at the High Court in Glasgow.
McCluskey was hit on the back of the head by McAuley in the attack and when he fell onto a bed he was hit repeatedly by the weapon.
McAuley then took a photograph of his victim, who was lying on his back on the bed either dead or dying, and sent it to his then-girlfriend.
Detective Inspector David Wagstaff, from Greenock’s Criminal Investigations Department, said: “This was a brutal attack and one that has left Kevin’s family absolutely devastated.
"I hope this conviction has given his family some sense of justice although due to McCluskey's actions, they will have to live with the loss of a much loved son and brother.
“I would also like to thank those who assisted with vital information in relation to our investigation."
Sentencing will be carried out at the High Court in Edinburgh on 28 January.