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backlight (in photography, etc.); illumination (of the subject) from behind
逆光で人物がシルエットになった。
The person became a silhouette in the backlight.
逆光撮影は難しいが美しい効果がある。
Backlight photography is difficult but has a beautiful effect.
逆光を避けて位置を変えた。
I changed position to avoid the backlight.