TikTok dumbfounded by color-changing hat

A woman has left TikTok speechless with her optical illusion of her wool hat changing colors.

No, this is not another The Dress situation like in 2015. TikToker Otelia Carmen (@oteliacarmen) shared a video that showed how her hat could apparently change colors depending on the lighting.

“So I bought this green hat at the store today, and I brought it home, and when I took it out, I was like, ‘Why is this brown?’” Carmen said in the clip. “Then realized: metamerism. This is why lighting is so important in interior design.”

@oteliacarmen

Why lighting should be just as important as color/material selections!! #interiordesign #learnontiktok #designertips #colortheory #shopwithme

♬ Do It To It – ACRAZE

Metamerism is when the color of an item changes because of different spectral emissions from various light sources. Light sources have their own “colors,” so when it’s projected onto another surface, it can impact the color of that surface.

It’s best explained when watching Carmen’s video. In this case, Carmen’s hat appeared green in the store’s lighting, but at her house, the lighting sometimes made it look red and, at other times, brown.

Even within her own house — depending upon the room’s lighting — Carmen’s hat changed colors.

Ultimately, to see what the true color of the hat was, Carmen took it outside into natural lighting and revealed that it’s really brown.

@oteliacarmen

Reply to @shaunmacl The magic hat in natural daylight, not what I expected 😅 #colortheory #metamerism #dayinmylife #shopwithme #STEMtok

♬ Stuck in the Middle – Tai Verdes

“The magic hat in natural daylight,” Carmen captioned the follow-up video. “Not what I expected.”

One commenter even backed up Carmen’s statement about metamerism.

“As a color designer in apparel, I can tell you it is SO important to double-check your dyed materials under different light sources!” they explained.

Others were baffled by the phenomenon — and not totally convinced it was real.

“I truly thought this was going to be about her being colorblind, but now I’m just confused,” someone wrote.

“WHAT IS HAPPENING?” another asked.

“I understand why it happens,” a viewer said. “My brain just can’t accept it.”

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