She woke up one morning 16 years ago with an itchy left eye. Over time, her vision worsened and the condition spread to her right eye. She eventually learned she had keratoconus, a degenerative eye disorder that caused her cornea to change shape. She received a cornea transplant, which restored limited sight.
Today, she is still considered legally blind. However her lack of sight hasn't left her in the dark. She is an avid photographer and her photos, which she shares on Flickr, are beautifully composed, vivid and clear.
Through her photography, she wants to show others what she sees.
"I never see photos the way others see them," says McCallum. "Sometimes I can barely see what I'm taking."
She points to two figures approaching her, one of whom is wearing dark-coloured pants. To her, that person's legs blend into the sidewalk, and the torso seems to float independently.
She looks back down at the sidewalk, because the sun is too bright for her eyes despite her sunglasses.
Sunsets and animals are among her favourite subjects to photograph. She sold her first photo an image of a Great White Egret to a fellow Flickr member earlier this year.
McCallum knows how to walk through a forest without scaring away wildlife (the key, she says, is to not be rushed). She can crouch in wait silently for hours to snap a photo of a Great Blue Heron, her favourite subject.
"If [the animals] are at a certain distance, I can see something there, but I can't always see them perfectly," says McCallum, who uses a manual focus lens. "I have to zoom in to see them. I think it's quite amazing, because I can't see when I'm taking the picture."
She also doesn't own Photoshop or any other image-processing software. Having used a film camera for several years, she's not accustomed to editing her photos.
"I prefer the photos to be as they are, and not played with too much," she says.
McCallum first knew she wanted to be a photographer when she played with a Polaroid camera at age 11. She would visit a forest in L'anse Ö l'Orme and pretended to snap pictures.
She didn't take up photography, since she was often told it wouldn't lead to a steady job. "I went to school to do office work," she says. "Right after I finished, my eyes went bad."
Today, she says, she counts her poor vision as a blessing. "I would not have been happy doing that kind of work," she says. She now has time to practice her photography.
But it took 10 years for her to reach that point. When she first lost her vision, she became depressed and rarely left her house.
"I was shy when I was young," she recalls. "Whenever I went to the store, I would ask someone to go with me. I was starting to get more confident, but then this happened. I had to ask people to come with me because I couldn't see what I was doing."
"After having this [vision] problem for 15 or 16 years, you get used to things," she says, chuckling.
Through her lens
McCallum has tried wearing glasses, but they distort her vision whenever she turns her head, making her feel nauseated. Instead, she wears sunglasses, since her eyes are sensitive to light. She does not use a cane to walk.
After receiving a cornea implant, she developed severe astigmatism. Her cornea is still shaped like a cone, and her right cornea is riddled with valleys, "so they can't even make a lens to fit it perfectly," she explains.
"I don't think I'd change anything," says McCallum. She only wishes other people could see through her lens.
McCallum is not alone. She recently discovered a community of blind photographers on Flickr. Like them, she enjoys the idea of sharing what she sees.
When most people view her work, McCallum says they can hardly believe she has any "eye problems." Nor would anyone believe it if they saw her kayaking.
"I do that to get closer to the animals so I can take a picture," she says, recalling the first time she tried to rent a kayak.
"They swore I'd tip it over," she says. She proved them wrong.
View more of her work at http://www.wix.com/christinaanne_m/photography