Jason Blum, king of the micro-budget horror film, had a clear message for fellow producers Saturday: don’t stop shooting.

“Don’t wait for the movie business to validate you… shooting begets shooting,” he asserted at a “360 Profile” panel on his Blumhouse Productions company at the Producers Guild of America’s 7th annual Produced By Conference on the Paramount lot.

Blum should know. He produced 2009’s landmark “Paranormal Activity” for $15,000 and saw worldwide grosses reach nearly $200 million, giving rise to the “Insidious,” “Sinister” and “The Purge” franchises. He also received an Academy Award Best Picture nomination this year for “Whiplash.”

The 75-minute session, attended by about 300 at the Sherry Lansing Theater, was aimed at giving an in-depth look at the nuances of how Blumhouse manages to be one of Hollywood’s most prolific producers with 15 films and three TV series shot last year.

“There’s a real correlation between not spending a lot of money and having fun,” he added.

Blum explained that on his films, directors have creative control within the parameters of the budget; that shoots are nearly always in Los Angeles and relatively brief; and crews aren’t required to work excessive hours. That means Blumhouse is able to rely on using high-profile actors and directors along with experienced crew.

“For actors, there’s a lot to be said for 4 weeks instead of 10 and shooting in LA instead of Romania,” he noted. “We work with high-level directors like Brad Peyton and Eli Roth because we do it on their schedules.”

The panel included Blumhouse’s production chief Jeanette Volturno-Brill, TV chief Jessica Rhoades and post-production head Phillip Dawe — who offered a succinct bit of advice to filmmakers: “Get the ending right.”

Blum asserted that Blumhouse will remain mainly a horror specialist with the occasional exception such as “Whiplash.” He recalled that the involvement of Jason Reitman as an exec producer changed his mind on bringing Blumhouse on board “Whiplash.”

“I said I thought it was OK and said ‘we’re never making this movie,'” Blum recalled.

Roth, who moderated the panel, noted that he had made a contribution to “Whiplash” by giving work to director Damien Chazelle several years earlier.

“I hired him when he was working as a math tutor to write ‘Last Exorcism 2,'” Roth explained. “That’s the money he used to make the ‘Whiplash’ short.”