A pensioner who downloaded and made almost 12,500 indecent images of children was caught out by a workman in his home.
George Thompson's activities came to light after a painter and decorator was doing some work at his premises in West Kirby.
Police were notified and when they raided his home in Hilbre Court, South Parade, West Kirby, they found a total of 12,428 illegal child porn pictures.
Kate Morley, prosecuting, told Liverpool Crown Court that 79-year-old Thompson had used a programme which had wiped most of his internet history and had a further anti-encryption program which made it difficult for police to forensically examine his computer.
He said he had collected the images from the internet and created some images himself by transferring the heads of some children onto the bodies of others.
Thompson said he gained sexual gratification from the pictures but they were for his own use and he had not shared them with anyone else, said Miss Morley.
He pleaded guilty to 16 charges of possessing and creating indecent images of children. The majority were in the lowest category of seriousness but included hundreds at the next three levels.
Thompson, who walks with two sticks, has previous convictions for indecently assaulting boys under the age of 14 in the 1950s and 1970.
Judge Andrew Hatton said he bore in mind Thompson posed a “limited risk” in the future and that he had admitted his guilty straight away.
“In my judgement the offences to which you have pleaded guilty merit a custodial sentence, but I think the long-term interests of society are best served by you being made the subject of supervision in the community.”
He imposed a community order with three years' supervision and ordered him to attend the Northumbria sex offenders programme.
Quentin Neal, defending, said the 12 months he had spent on bail was a “period of trauma” and that since his last conviction he had built up status in the community which he had now lost.
“To a large extent he has subdued the demons in his personality. He feels shamed by his offending,” he added.