Kate Parker is standing in front of a picture window deciding if she has found the best light. The Atlanta-based photographer is prepping for a photo shoot and knows that light -- the kind you find or the kind that finds you -- can make or break an image.

Parker, who created an international sensation with her "Strong is the new pretty" photo series, has spent the last two years both in front of and behind the bright lights of celebrity.

The photographs she shot of her two daughters -- then ages 6 and 3, in all of their rough and tumble greatness -- have since turned into a massive book project featuring images and quotes of 300 girls nationwide, all of whom offer some vision of strength.

"I wasn’t shooting to start this project," said Parker of Roswell. "I was just shooting [my girls and their friends] as they were."

Girls in uniform leaning on a brick wall with eye-black stickers under their eyes. Girls jumping, leaping and swimming underwater. Girls coasting down streets on bikes, Big Wheels and roller skates wearing skirts, helmets with kitten ears and big smiles. Girls looking at worms or dancing in the rain.

The images, she said, were a reminder to the girls to be who they are.

"I think girls, up until puberty, think they are badasses and then everyone tells them they are not. Maybe you will have this group of images to tell them, 'look at how cool you were and look at how great you are,'" Parker said.

The project has led to many related projects including a collaboration with Special K called "Nourish Your Next."

Last month, Nourish awarded Parker with a pop-up gallery exhibition in New York City, for which Parker photographed actress, comedian and Special K celebrity spokeswoman, Tracee Ellis Ross.

This month, Parker is also photographing three women for the campaign who will each receive $10,000 to support their non-profit organizations.

Kimberly Bryant, a former biotech worker, founded Black Girls Code in 2011 which introduces girls from underrepresented communities to coding. Maria Rose Belding, 20, created the MEANS Database , a website that helps reduce food waste and feed the hungry and Erin Regan helped launch and lead the Los Angeles County Fire Department's Women's Fire Prep Academy and Girl's Fire Camp.

Parker, essentially a self-taught photographer, had worked in video editing at CNN and production at the ad agency JWT, before launching a family photography business. Then she participated in a group show at Mason Maurer gallery.

It was her first gallery show and she had to cull through her many images to tell a story. "They went into the gallery and I was so proud of them but nothing sold," she said. It was a strong group of images that she knew told a story, but she wasn't sure what the story was.

"I thought I would send them out to a few blogs I had read," said Parker. She got picked up by a popular blog, which then led to a call from the Huffington Post. After the interview, when the writer coined the phrase "strong is the new pretty" everything clicked for Parker.

"It was about girls being allowed to be themselves and not what they are expected to be. It was a lightbulb moment. I started shooting around that," Parker said.

It didn't take long for the striking black and white images to get even more attention. Parker's work appeared in international publications, she did interviews and she was getting letters like the one from a 12-year-old girl in France whose mother would not allow her to play soccer until the girl showed her mother Parker's images, which for some reason, made the woman change her mind.

It was more attention than Parker had ever anticipated and it wasn't always good. Parker was surprised at the criticism aimed at her and her family.

People weighed in on her appearance saying the petite, blonde Parker could never understand how it felt to be on the other side of society's standards. They criticized her for wearing makeup, accused of her trying to turn young girls into lesbians, and suggested she was compromising the health of her own children with some of the images. Her daughter standing under a hand-dryer, for example, could cause hearing loss and spread germs, said one viewer.

It was a blow to Parker, the youngest of four kids, who had grown up as a soccer playing tomboy idolizing her two athletic, older brothers.

Parker soon learned to ignore the trolls, except in one case where she felt her critics made a valid point.

She was photographing her girls who are very much like her when she was a young girl. "They weren’t athletic yet, they just weren't into princesses. They liked balls and running around. They were barefoot and adventurous and did not like to take showers. I didn't want them to lose it because society told them that was the right way to be," said Parker.

But what about the young girls who are artists like Parker's sister and mother or girls who are musicians or into math and science? They were no less strong, and Parker realized she needed to show that as well.

"The images are so in your face and impactful that you have to show the other side," she said. "It was a fair criticism and I felt I needed to incorporate it into the work. If you are showing strength you need to show the musicians, the cancer survivor and all kinds of strong girls."

So Parker went in search of girls with every kind of strength. She found a 16-year-old pilot who has made solo flights, a 10-year-old Vans wearing professional skateboarder and a 12-year-old amputee who opted for a special operation that placed her foot in reverse position at her knee so that she would still have a joint and be able to continue playing sports.

The book, which will be released in March 2017, will feature girls who do everything under the sun, from every demographic group, said Parker. While she still gets suggestions on social media, it is almost always something she already has represented.

Parker, whose next project is a series on the different ways we define family, says she wants her work to help normalize her subjects whether it makes it okay for girls to go hard at whatever they love to do or for families to blend and find form in whatever ways feel right.

In either case, it takes a lot of strength to go your own way.

"Strength is individual. It is rising up against adversity in whatever form that takes. It could be quiet or loud or emotion or art. It is really individual," said Parker. "These girls have inspired me so much."