When the date of creation is written somewhere on the image, usually next to the artist name.
Do not use year-specific tags (such as 2018) for dates in pictures, unless the picture is centered around the year itself (such as in New Year pictures and other festivities).
For when the date is written in the commentary, use dated commentary instead.
Use timestamp for times or dates shown in images that don't have anything to do with date of the image's creation (for example, dates shown in recordings).
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