Heidi Klum explains those topless beach photos

Heidi Klum was spotted ditching her bikini top during a recent secluded beach day with boyfriend Vito Schnabel in the south of France, and the stunning supermodel says she's always surprised by how the paparazzi find her during her most intimate and revealing moments.

"You have to understand -- I go on a boat for like an hour and a half to try and find the most secluded piece of beach where there's literally nobody," Klum told ET's Cameron Mathison at the Billboard Music Awards red carpet in Las Vegas on Sunday. "I don't know how the [paparazzi] do it. They come with like the SCUBA thing!"

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The 42-year-old "America's Got Talent" judge was snapped beachside in Pampelonne, Gulf of Saint-Tropez with her 29-year-old beau last Wednesday. Klum rocked a large pink hat and dark glasses to shade her face from the sun, but went sans top to catch some rays and go for a dip in the Mediterranean waters.

"I never see [the photographers] and I think we're all by ourselves," Klum continued. "It's not like I'm going topless on a public beach with lots of people around."

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The famed fashionista admitted that she wasn't too bothered by the revealing photos. "I'm from Germany," Klum explained. "We are not as uptight if you don't wear a top."

While Klum has been in a relationship with Schnabel since 2014 -- two years after Klum filed for divorce from her ex, Seal, with whom she had been married since 2005. Klum and Seal both walked the red carpet at Sunday's BBMAs, but the two seemed to avoid each other in front of the cameras.