By Stephanie Stahl

PHILADELPHIA (CBS) —  What color is the dress?  It’s the great debate that’s exploded on the Internet, trending number one with some seeing blue and black. Others say it’s white and gold.

It started with a picture posted on Tumblr and it quickly turned viral millions of people still seeing different colored dresses.

Vision comes from tiny cones in the back of the eye on the retina that gets interpreted by the brain. You know the saying “your mind’s eye?” That could be why we’re seeing different colors with the dress.

This is the blue and black dress that has 28 million views on Buzzfeed. Some see a white and gold dress.

We turned to the experts at Wills Eye Hospital. Still no consensus. I saw the dress as blue and black, Ophthalmologist Mitchell Fineman saw white and gold.

“We’re going to have to agree to disagree.”  Dr. Fineman says. He  teaches visual physiology at Wills Eye Hospital. He says brains process colors differently. “And it’s influenced by a lot of things. If you see one color in bright daylight or a color in a room where there is a LED light bulb where there’s a more bluish tinge, you can see the same color differently,” Dr. Fineman explains.

Color perception also depends on contrast and background color. With the dress – the real one is in the middle, but different views show color variations. “For whatever reason, the colors in this dress really highlight that processing that goes on in the brain and therefore there’s a lot of discrepancy to what people see,” Dr. Fineman says.

He adds, “It just sort of accentuates the fact that beauty is in the eye of the beholder. So we see the same thing in a different way.”

In one unofficial poll, three-fourths of people swore the dress was white and gold, only a fourth saw the actual color blue and black.

Some think the dress even changed colors. There’s no seeing eye to eye on this one. The maker of the dress has experienced a 347 percent increase in sales.