A Florida man accused of making pornographic images of his three young daughters claims he and the girls are nudists, and the photos are simply family portraits.

A judge on Wednesday found the images of the girls, aged 8 to 12, were suggestive enough that Brian Martens, 53, a former resident of the Sunsport Gardens Family Naturist Resort in Loxahatchee Groves, Fla., should stand trial.

"Several of these photos the court has reviewed are lascivious. … They are, in the court's opinion, sexually explicit," federal magistrate Judge Bill Matthewman said in court on Wednesday.

Martens did "persuade, induce and entice a minor to engage in sexually explicit conduct for the purpose of producing a visual depiction of such conduct," according to a federal indictment obtained by ABCNews.com.

Martens did not take the photos himself but hired a professional photographer. That man, Leslie Grey Vanaman, was tried and convicted of child porn and is currently serving a 60-year sentence.

None of the images depict sexual acts. One image is a close-up of one girl's genitalia, according to prosecutors.

In court Wednesday, Marten's attorney claimed his client did not know Vanaman had taken the close-up shots, and the images were otherwise appropriate for a family of nudists.

"The girls have no clothes on … but they're not doing anything of a sexual nature," Marten's lawyer, James Eisenberg, said in court on Wednesday, according to the Sun Sentinel. "If they were young ladies who had clothing on, no one would consider them pornographic."

"Totally nude … is the normal state of all the people who live there," Eisenberg said. "In the context that everybody in this family are naturists … these photos are not lewd or pornographic in any way."

Eisenberg was traveling and was not available to comment to ABC News.

Martens was arrested on Oct. 29. If convicted he faces a maximum sentence of 30 years for producing child pornography, and an additional 20 years if convicted of receiving child porn, according to the federal indictment.

He has pleaded not guilty to the charges.