Gavin Charlton’s girlfriend reported him after finding erotic pictures of an underage girl on his mobile phone.
Police later found more images on his computer and Charlton pleaded guilty at Teeside Crown Court in February to eight charges of making indecent images of a child and five of taking indecent pictures.
The university graduate, of Wilson Drive, Rotherham, who previously lived on Teeside, was jailed for 18 months.
But the Appeal Court cut his sentence to 14 months after hearing that the six images on his phone and the 174 on his computer were all at the lowest end of the scale, showing naked children but with no sexual activity taking place.
His lawyers argued that the original sentence had been more appropriate for someone involved in producing images for commercial gain.
But their claim that he should have been given a suspended sentence was rejected.