Often said when you second guess your (or someone else's) initial impression of something/someone.
Usually, I find him ugly, but today he's smokin' hot. Must be the lighting.

She looked hot on instagram, but then I met her IRL. Must've been the lighting.

Person A (who is overweight): I look so skinny today.
Person B: It must be the lighting.
by libelula_안녕 July 17, 2018
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