Here We Go Again: People Are Debating Whether a Photo Is of a Beach or a Door

First, there was the dress. Then, internet users debated over Yanny versus Laurel.

Now, once again, people across the country are divided by an optical illusion.

Is this picture of a beach, or a door?

Uploaded late last week by a Twitter user named @rebeccareilly__, the image shows three strips of color — one a dark blue, the middle a teal green, and the last a beige. Looked at the picture from the side, the image appears to mimic the colors of a beach getaway.

Alongside her inquiry over whether the image was sand or a building exit, Becky wrote, “Hahahaha.”

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The photo has been retweeted around 20,000 times, with countless responses. The Twitter user also uploaded a poll asking people to vote with their answer — and as of Friday afternoon, the response was pretty evenly split.

Becky eventually cleared up the debate, posting the same image horizontally and revealing that it was a beach. In the reveal image, there appeared to be people in the water.

Related Video: Voice of 'Yanny vs. Laurel' Revealed What He *Actually* Said

Still, social media users were divided. Some argued that the reveal image had been photoshopped to include beachgoers.

Optical illusions like the beach — or door — have been popular on the internet for years. The trend kicked off in 2015 with a photo of a dress that some people saw as blue and black, while others insisted it was white and gold. At the time, the confusion was explained by many people are merely science.

The difference in hues was ascribed to something called “color constancy,” where our brains compensate for differences in lighting and white-balance by automatically filling in information.