Imposing a jail sentence on a 55-year-old Adelaide man for two child porn offences, Judge Rosemary Davey said if there was no market for such vile images and videos there would be no need for people to create them.

But she said that because there were people trying satisfy their prurient interests, the court had to ensure penalties reflected the need for general deterrence.

"We are now seeing these cases regularly before the courts," Judge Davey said as she jailed Douglas Spinks for 18 months.

The man's offending related to three videos and other images found on his computer.

He subsequently pleaded guilty to one count of aggravated possessing child pornography and one count of possessing child pornography.

Judge Davey said all the images and videos were vile but some depicting young girls were particularly repulsive.

She said Spinks' offending was serious and the images were degrading to the children involved.

The judge imposed a non-parole period of 12 months.