A former teacher who filmed dozens of pupils using hidden cameras set up at a boarding school has been jailed for more than three years.
Jonathan Thomson-Glover, 53, who taught at Clifton College, in Bristol, admitted 36 counts of making, taking and possessing indecent images of children.
Taunton Crown Court heard 130 victims were filmed with secret cameras at the school and an address in Cornwall over a 16-year period.
Thomson-Glover recorded more than 2,500 hours of footage to spy on pupils aged around 12 to 17 as they engaged in sexual activity and used the bathroom.
He was caught after the National Crime Agency (NCA) traced an IP address used for downloading indecent images of children to one of his four computers.
There is no suggestion Thomson-Glover, who described his filming as "a compulsion fuelled by the internet", shared his footage or made physical contact with pupils.
Judge David Ticehurst jailed the teacher, who bowed his head throughout proceedings, for three years and nine months.
"This activity took place while you were a highly respected and trusted teacher at a school in Bristol," the judge said.
"You are a man looking at a life that is now in ruins," he continued. "That life was a good life and you have made a positive contribution.
"It is impossible to calculate the harm and damage you may have caused to those who trusted you or were in your care."
Thomson-Glover admitted 27 charges of taking an indecent image of a child; seven charges of making an indecent image of a child and two charges of possessing indecent images of children.
He was ordered to sign the Sex Offenders Register indefinitely and banned from working with children.
Prosecuting, Howard Phillips read victim impact statements from seven pupils and three parents.
One said: "I feel a great deal of shock and sadness, and the consequences of this abuse will stay with me for a long time."
Mr Phillips said pupils described Thomson-Glover, who allowed them to smoke, drink and have sexual relationships on school premises, as "more a friend than a teacher".
The court heard Thomson-Glover met parents of the school following his arrest, with some writing letters of recommendation to the judge on his behalf.
One mother wrote: "I met a man who was deeply sorry and contrite."
Andrew Langdon QC, representing Thomson-Glover, said his client had realised he was gay as a teenager but repressed his sexuality.
He later began working at Clifton College and installed the cameras after viewing images on the internet.
Mr Langdon said the majority of footage recorded was never watched, with pupils filmed engaging in sexual acts aged 16 or 17 at the time.
Speaking after the case, Detective Inspector Andrea Kingdon, of Devon and Cornwall Police, said: "These crimes amounted to an abhorrent abuse of trust and a gross invasion of privacy.
"He's proved himself to be a manipulative and devious sexual offender who had the ability to keep his compulsion a secret from everyone around him."
A spokeswoman for Clifton College said the discovery of Thomson-Glover's activity had been "profoundly disturbing".
She said a series of reviews, including an external safeguarding review, had been carried out as well as physical searches of college buildings but no cameras had been found.