Sometimes visual problems are noted only in certain lighting conditions (i.e. light vs. dark or day vs night). (maxshelpingpaws.org)
The shimmer effect is very subtle, but does stand out more in certain lighting conditions. (wacie.com)
Have you ever taken a photo or seen yourself in the mirror under certain lighting conditions, and noticed that the concealer under your eyes looks especially noticeable? (simplystine.com)