Robert Welch, 63, was given a community order this week for sexual offences including making indecent images of children and possessing extreme pornographic images involving animals.
The Telford man, who previously served in the RAF for more than 20 years, hid in a bush and filmed a children's playground while making vulgar comments, Shrewsbury Crown Court heard.
Although that incident did not make up any of the offences he was sentenced for, Welch also discussed child abuse and shared images online with others over Twitter, including a couple from Germany.
The court heard on Wednesday from prosecutor Ms Alexandra Bull that the offences, which included making indecent images, distributing images and possessing extreme pornographic images, took place between early 2018 and August of this year.
They involved about 500 indecent images of children, most of them in the least serious category (category C), as well as a small number of extreme images involving animals.
He shared images and messages over Twitter that indicated an interest in underage girls, the court heard.
Ms Bull told the court that an account traced to Welch's Telford address was involved in sharing indecent discussions and images with other accounts, and that in one video which was found he "appears to be hiding in a bush close to a playground" filming children playing and making vulgar comments about girls he could see.
Later, when police visited to speak to him he told them: "It's just Twitter," the court heard. His devices were searched and hundreds of images were found.
The children in the images were aged from eight to 14.
Welch, of Shawfield Close in Sutton Hill, was interviewed by police and admitted to offences of making indecent images, distributing indecent images and possessing extreme pornographic images.
This week he was represented in court by Miss Debra White, who said that he had served in the RAF for more than 20 years before moving into civilian life, and that his wife had died in 2006.
She said that he was remorseful and felt "disgusted" at what he had done.
Judge Peter Barrie handed down a community order, meaning Welch will have to complete 130 hours of unpaid work and an accredited sexual offenders' programme.
He will be subject to a sexual harm prevention order and a notification order, restricting his internet activity and compelling him to tell police if he re-locates.
The judge told him that that it was important to punish people who use children for sexual gratification, and that if any of the children that he filmed later learned of the videos he made of them, they would be "horrified and disturbed".