An oil industry boss who downloaded nearly 50,000 indecent images of children has escaped a jail sentence after sharing details of his online paedophile network with police.

Liam Gibson, 56, used file-sharing software to exchange photographs on a secretive social networking site.

Police found 49,809 images, most of which showed children aged between five and 14, on his computer when they went to his home in Pathhead, Midlothian, after receiving a tip-off.

Gibson, a former merchant navy seaman who went on to make a fortune with his own oil business, was sentenced to three years' probation and 150 hours community service after Edinburgh Sheriff Court heard he had co-operated fully with police.

Defence QC Gordon Jackson told Sheriff James Scott that Gibson provided valuable details to detectives investigating online paedophile activity.

He said: "We know that the police are content with his level of co-operation and with what he has told them.

"They have found the information to be helpful. We do not know whether there have been arrests in somewhere like Sheffield as a consequence of what he has told them - that is secret, confidential information.

"But what I can say is that his information has greatly assisted them."

Gibson owns Gibson Marine, which operates throughout the world transporting rigs to oil fields. The court heard he was one of the few people in the world with the technical expertise to move oil rigs.

"He is thought to be one of the world's best in a highly specialised sector," Mr Jackson said. "He is a world renowned expert."

The QC added that Gibson's marriage broke down after his arrest: "I'm the last person to parrot nonsense like this is a victimless crime. But this is had some consequence on his personal life."

Gibson pled guilty in May 2011 to charges of possessing indecent images of children.

Sheriff Scott warned him that he risked going to prison if he accessed similar pictures again.

He said: "I am persuaded that the most appropriate way to deal with this is to impose a probation order.

"The probation order for a period of three years. You will also perform 150 hours of unpaid work in the community."