Freediver, PFI Freedive Instructor, Safety Diver, Analog & Digital Photographer, Creative Director
Portrait by Perrin Franta
Katharine Kollman is a photographer and freedive instructor exploring the relationship between humans and the underwater world. Rooted in the liminality of the ocean, her work examines the tension between presence and impermanence, using black-and-white film to distill the shifting textures and ephemeral moments found beneath the surface. Through her imagery, she seeks to conjure both reverence and reconsideration—reminders that the sea is not so far removed from our own, human existence.
Interested in the ways people engage with water beyond recreation, Katharine often collaborates with fellow divers, examining the rituals, adaptations, and instincts that define human interaction with the water. Her background in freediving and teaching allows her to navigate these submerged spaces with intention, moving fluidly through environments where control is an illusion.
Working primarily within the analog process, Katharine develops and prints her images in her own at-home darkroom, ensuring that each piece is shaped by her hands from start to finish. Her work has been exhibited internationally and acquired by institutions such as the Kiyosato Museum of Photographic Arts.
She is certified with Performance Freediving International and currently based in Honolulu, Hawai‘i.
casse-cou - /kasku/ French, meaning “daredevil”, or “reckless person”
the term stems from “casser le cou”, which literally translates, “to break the neck”
Having started learning French at an early age and pursuing it through university, the language remains close to Katharine’s heart. When she first began sharing photography on social media, uncertain of where it might lead, she chose to use a nom de plume rather than her own name.
Cassec0u became a kind of artistic alter ego—offering a way to step beyond self-doubt and embody the confidence to share her work with the world. You can read more about it here.
“La mer imite le bruit du bonheur”… “the sea imitates the sound of happiness”
— Régis Jauffret
Photos by Perrin James, Lenny Kaholo, Estelle Wild, Terry Flanagan