Antony Bonaccorso appeared at Parramatta District Court on Friday after seeking out his victims on Snapchat.
After asking them for photos, he then inserted the phrase "f*** me daddy" onto those images and threatened to send them to friends and family if the women did not send him further material.
Judge Stephen Hanley found that while three targets - women aged 15, 26 and one under 18 years old - did not respond to his threats, this was still harassment, the judge said.
"I'm going to f*** you whether you like it or not," Bonaccorso told the 26-year-old after she said she would not sleep with him.
On a separate occasion, a 15-year-old girl panicked and sent Bonaccorso photographs of herself both naked and in her underwear.
"The child abuse material was only produced because she responded to his verbal threats," Judge Hanley said.
Bonaccorso also tried to seek explicit images in this way while chatting to an undercover police officer posing as a 14-year-old girl on Snapchat.
He asked the purported teen for images of her breasts and suggested they could meet and have a shower together.
The 25-year-old had also downloaded around 300 images and videos showing pre-pubescent boys and girls engaging in sexual activity.
However, this was not a lot compared to other cases where thousands of pieces of child abuse material were found, the judge said.
Bonaccorso had pleaded guilty in March and had shown remorse for his actions including through a moving and genuine letter to the court, Judge Hanley found.
"I'm deeply ashamed and deeply sorry to all the victims," the 25-year-old wrote.
Bonaccorso had also taken great steps towards rehabilitation after being diagnosed with depressive disorder, anxiety and PTSD from past trauma.
He had strong support from his parents, who appeared in court on Friday, as well as his fiance and friends, the judge found.
While convicting Bonaccorso and imposing a sentence of three years, the judge took into account the 133 days he had already spent in custody before being bailed, subtracting this from the total sentence.
Finding that his positive progress towards rehabilitation would be severely affected by being sent to prison, Judge Hanley said he could remain in the community under a recognisance release order.
He is to be on good behaviour for five years and to remain under the supervision of a probation officer while he continues his mental health treatment.
He was also ordered to pay a fine of $1000 and a further amount of $1000 as security which will be forfeited if the terms of the release order are breached.
If that happens, Bonaccorso could be imprisoned for the remainder of his sentence.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
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