It could be the clue that helps identify whether or not a young child has a serious eye disease.
It is something Karmark wishes he knew about sooner.
"In Jonathan's case, it's hard to know for sure, but there is always that chance that we could have at least saved some of his vision," said Karmark.
'Red eye' in photos indicates healthy eye
If there's red in the pupil, that's normal. But if there's a white or gold glow present, it could be the indicator of one of many eye diseases, including cancer.
Karmark didn't know this before his three-year-old son was diagnosed with Coats' disease, a rare condition that causes abnormal blood vessels to develop behind the retina.
"We noticed in the late spring of 2013 his eye appeared to be lazy. It was turning out to the side of his face."
So Karmark and his wife took Jonathan to an eye specialist. Before that, they had no idea how severe their son's case was.
Parents notice eye glow after diagnosis
It has left Jonathan without vision in one eye. Knowing the indicators now, when Karmark looks back at photos of Jonathan, he can see the glow.
"We did some research on the internet. We realized that Jonathan had had the glow several months before he had the lazy eye," said Karmark.
"So from that point, we obviously came to the conclusion if we had known sooner to look for the glow and not just slough it off as a dodgey cell phone camera that we would have taken it more seriously and perhaps taken immediate action."
Dr. Nigel Rawlings is a retina specialist in Saskatoon, who says getting the information out to the public is important.
"If more parents know about this, it could eventually be a lifesaving or eye-saving intervention for some people in the future," said Rawlings.
The glow can also occur in adults. However, Rawlings said they typically notice vision problems and can report it themselves.
According to Know The Glow, looking for the gold or white glow in photos is particularly important in children who are too young to indicate something is wrong with their vision.
Jonathan 'a happy active three-year-old'
Karmark said Jonathan is doing much better and is a happy three-year-old.
"The only thing we have noticed is that he'll bump into things on occasion on his right hand side because he can't see."
Jonathan's other eye is completely normal, but he wears special glasses to protect it.
"It took a lot of candy but he so far seems to have adjusted," said Karmark. "Now he has to have a lot of fillings, so I guess there was a price to pay for that too."